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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

FORM 10-Q

☒QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended September 30, 2019
or
☐TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from to
Name of Registrant, State of Incorporation, Address of Principal Executive Offices, Telephone Number, Commission File Number, IRS Employer Identification Number
ALLIANT ENERGY CORP ORATION
(a Wisconsin Corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 1-9894
IRS Employer Identification Number - 39-1380265
INTERSTATE POWER & LIGHT CO MPANY
(an Iowa corporation)
Alliant Energy Tower
Cedar Rapids, Iowa 52401
Telephone (319) 786-4411
Commission File Number - 1-4117
IRS Employer Identification Number - 42-0331370
WISCONSIN POWER & LIGHT CO MPANY
(a Wisconsin corporation)
4902 N. Biltmore Lane
Madison, Wisconsin 53718
Telephone (608) 458-3311
Commission File Number - 0-337
IRS Employer Identification Number - 39-0714890
This combined Form 10-Q is separately filed by Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company. Information contained in the Form 10-Q relating to Interstate Power and Light Company and Wisconsin Power and Light Company is filed by each such registrant on its own behalf. Each of Interstate Power and Light Company and Wisconsin Power and Light Company makes no representation as to information relating to registrants other than itself.
Securities registered pursuant to Section 12(b) of the Act:
Alliant Energy Corporation, Common Stock, $0.01 Par Value, Trading Symbol LNT, Nasdaq Global Select Market
Interstate Power and Light Company, 5.100% Series D Cumulative Perpetual Preferred Stock, $0.01 Par Value, Trading Symbol IPLDP, Nasdaq Global Select Market
Indicate by check mark whether the registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days.
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐
Indicate by check mark whether the registrants have submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrants were required to submit such files).
Alliant Energy Corporation - Yes ☒ No ☐
Interstate Power and Light Company - Yes ☒ No ☐
Wisconsin Power and Light Company - Yes ☒ No ☐
Indicate by check mark whether the registrants are large accelerated filers, accelerated filers, non-accelerated filers, smaller reporting companies, or emerging growth companies. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Alliant Energy Corporation - Large Accelerated Filer ☒ Accelerated Filer ☐ Non-accelerated Filer ☐ Smaller Reporting Company ☐ Emerging Growth Company ☐
Interstate Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐
Wisconsin Power and Light Company - Large Accelerated Filer ☐ Accelerated Filer ☐ Non-accelerated Filer ☒ Smaller Reporting Company ☐ Emerging Growth Company ☐
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Alliant Energy Corporation ☐
Interstate Power and Light Company ☐
Wisconsin Power and Light Company ☐
Indicate by check mark whether the registrants are shell companies (as defined in Rule 12b-2 of the Exchange Act).
Alliant Energy Corporation - Yes ☐ No ☒
Interstate Power and Light Company - Yes ☐ No ☒
Wisconsin Power and Light Company - Yes ☐ No ☒
Number of shares outstanding of each class of common stock as of September 30, 2019:
Alliant Energy Corporation, Common Stock, $0.01 par value, 240,342,949 shares outstanding
Interstate Power and Light Company, Common Stock, $2.50 par value, 13,370,788 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)
Wisconsin Power and Light Company, Common Stock, $5 par value, 13,236,601 shares outstanding (all outstanding shares are owned beneficially and of record by Alliant Energy Corporation)

Table of Contents
TABLE OF CONTENTS

| Page
Definitions | 1
Forward-looking Statements | 1
Part I. Financial Information | 3
Item 1. Condensed Consolidated Financial Statements (Unaudited) | 3
Alliant Energy Corporation | 3
Interstate Power and Light Company | 6
Wisconsin Power and Light Company | 9
Combined Notes to Condensed Consolidated Financial Statements | 12
1. Summary of Significant Accounting Policies | 12
2. Regulatory Matters | 13
3. Receivables | 14
4. Investments and Acquisitions | 15
5. Common Equity | 15
6. Debt | 18
7. Leases | 19
8. Revenues | 20
9. Income Taxes | 21
10. Benefit Plans | 22
11. Asset Retirement Obligations | 23
12. Derivative Instruments | 23
13. Fair Value Measurements | 24
14. Commitments and Contingencies | 26
15. Segments of Business | 28
16. Related Parties | 29
Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations | 30
Item 3. Quantitative and Qualitative Disclosures About Market Risk | 38
Item 4. Controls and Procedures | 38
Part II. Other Information | 38
Item 1A. Risk Factors | 38
Item 2. Unregistered Sales of Equity Securities and Use of Proceeds | 38
Item 6. Exhibits | 39
Signatures | 39

Table of Contents
DEFINITIONS
The following abbreviations or acronyms used in this report are defined below:

Abbreviation or Acronym | Definition | Abbreviation or Acronym | Definition
2018 Form 10-K | Combined Annual Report on Form 10-K filed by Alliant Energy, IPL and WPL for the year ended Dec. 31, 2018 | GAAP | U.S. generally accepted accounting principles
AEF | Alliant Energy Finance, LLC | IPL | Interstate Power and Light Company
Alliant Energy | Alliant Energy Corporation | IUB | Iowa Utilities Board
ATC | American Transmission Company LLC | MDA | Management’s Discussion and Analysis of Financial Condition and Results of Operations
ATC Holdings | Interest in American Transmission Company LLC and ATC Holdco LLC | MISO | Midcontinent Independent System Operator, Inc.
Corporate Services | Alliant Energy Corporate Services, Inc. | MWh | Megawatt-hour
DAEC | Duane Arnold Energy Center | N/A | Not applicable
Dth | Dekatherm | Note(s) | Combined Notes to Condensed Consolidated Financial Statements
EGU | Electric generating unit | OPEB | Other postretirement benefits
EPA | U.S. Environmental Protection Agency | PPA | Purchased power agreement
EPS | Earnings per weighted average common share | PSCW | Public Service Commission of Wisconsin
Federal Tax Reform | Tax Cuts and Jobs Act | U.S. | United States of America
Financial Statements | Condensed Consolidated Financial Statements | Whiting Petroleum | Whiting Petroleum Corporation
FTR | Financial transmission right | WPL | Wisconsin Power and Light Company

FORWARD-LOOKING STATEMENTS
Statements contained in this report that are not of historical fact are forward-looking statements intended to qualify for the safe harbors from liability established by the Private Securities Litigation Reform Act of 1995. These forward-looking statements can be identified as such because the statements include words such as “may,” “believe,” “expect,” “anticipate,” “plan,” “project,” “will,” “projections,” “estimate,” or other words of similar import. Similarly, statements that describe future financial performance or plans or strategies are forward-looking statements. Such forward-looking statements are subject to certain risks and uncertainties that could cause actual results to differ materially from those expressed in, or implied by, such statements. Some, but not all, of the risks and uncertainties of Alliant Energy, IPL and WPL that could materially affect actual results include:

• | IPL’s and WPL’s ability to obtain adequate and timely rate relief to allow for, among other things, the recovery of and/or the return on costs, including fuel costs, operating costs, transmission costs, environmental compliance and remediation costs, deferred expenditures, deferred tax assets, tax expense, capital expenditures, and remaining costs related to EGUs that may be permanently closed and certain other retired assets, earning their authorized rates of return, and the payments to their parent of expected levels of dividends;

• | federal and state regulatory or governmental actions, including the impact of legislation, and regulatory agency orders;

• | the impact of customer- and third party-owned generation, including alternative electric suppliers, in IPL’s and WPL’s service territories on system reliability, operating expenses and customers’ demand for electricity;

• | the impact of energy efficiency, franchise retention and customer disconnects on sales volumes and margins;

• | the impact that price changes may have on IPL’s and WPL’s customers’ demand for electric, gas and steam services and their ability to pay their bills;

• | the ability to utilize tax credits and net operating losses generated to date, and those that may be generated in the future, before they expire;

• | the direct or indirect effects resulting from terrorist incidents, including physical attacks and cyber attacks, or responses to such incidents;

• | the impact of penalties or third-party claims related to, or in connection with, a failure to maintain the security of personally identifiable information, including associated costs to notify affected persons and to mitigate their information security concerns;

• | employee workforce factors, including changes in key executives, ability to hire and retain employees with specialized skills, ability to create desired corporate culture, collective bargaining agreements and negotiations, work stoppages or restructurings;

• | weather effects on results of utility operations;

| 1 |

Table of Contents

• | issues associated with environmental remediation and environmental compliance, including compliance with all environmental and emissions permits, the Coal Combustion Residuals Rule, future changes in environmental laws and regulations, including the EPA’s regulations for carbon dioxide emissions reductions from new and existing fossil-fueled EGUs, and litigation associated with environmental requirements;

• | the ability to defend against environmental claims brought by state and federal agencies, such as the EPA, state natural resources agencies or third parties, such as the Sierra Club, and the impact on operating expenses of defending and resolving such claims;

• | continued access to the capital markets on competitive terms and rates, and the actions of credit rating agencies;

• | inflation and interest rates;

• | the impact of the economy in IPL’s and WPL’s service territories and the resulting impacts on sales volumes, margins and the ability to collect unpaid bills;

• | the ability to complete construction of wind projects within the cost caps set by regulators and to meet all requirements to qualify for the full level of production tax credits;

• | changes in the price of delivered natural gas, purchased electricity and coal due to shifts in supply and demand caused by market conditions and regulations;

• | disruptions in the supply and delivery of natural gas, purchased electricity and coal;

• | changes in the price of transmission services and the ability to recover the cost of transmission services in a timely manner;

• | the direct or indirect effects resulting from breakdown or failure of equipment in the operation of electric and gas distribution systems, such as mechanical problems and explosions or fires, and compliance with electric and gas transmission and distribution safety regulations, including regulations promulgated by the Pipeline and Hazardous Materials Safety Administration;

• | issues related to the availability and operations of EGUs, including start-up risks, breakdown or failure of equipment, performance below expected or contracted levels of output or efficiency, operator error, employee safety, transmission constraints, compliance with mandatory reliability standards and risks related to recovery of resulting incremental costs through rates;

• | impacts that storms or natural disasters may have on Alliant Energy’s, IPL’s and WPL’s operations and recovery of costs associated with restoration activities, or on the operations of Alliant Energy’s investments;

• | any material post-closing adjustments related to any past asset divestitures, including the sales of IPL’s Minnesota electric and natural gas assets, and Whiting Petroleum, which could result from, among other things, indemnification agreements, warranties, parental guarantees or litigation;

• | Alliant Energy’s ability to sustain its dividend payout ratio goal;

• | changes to costs of providing benefits and related funding requirements of pension and OPEB plans due to the market value of the assets that fund the plans, economic conditions, financial market performance, interest rates, life expectancies and demographics;

• | material changes in employee-related benefit and compensation costs;

• | risks associated with operation and ownership of non-utility holdings;

• | changes in technology that alter the channels through which customers buy or utilize Alliant Energy’s, IPL’s or WPL’s products and services;

• | impacts on equity income from unconsolidated investments due to further potential changes to ATC’s authorized return on equity;

• | impacts of IPL’s future tax benefits from Iowa rate-making practices, including deductions for repairs expenditures, allocation of mixed service costs and state depreciation, and recoverability of the associated regulatory assets from customers, when the differences reverse in future periods;

• | the impacts of adjustments made to deferred tax assets and liabilities from changes in the tax laws;

• | changes to the creditworthiness of counterparties with which Alliant Energy, IPL and WPL have contractual arrangements, including participants in the energy markets and fuel suppliers and transporters;

• | current or future litigation, regulatory investigations, proceedings or inquiries;

• | reputational damage from negative publicity, protests, fines, penalties and other negative consequences resulting in regulatory and/or legal actions;

• | the effect of accounting standards issued periodically by standard-setting bodies;

• | the ability to successfully complete tax audits and changes in tax accounting methods with no material impact on earnings and cash flows; and

• | factors listed in MDA and Risk Factors in Item 1A in the 2018 Form 10-K.

Alliant Energy, IPL and WPL each assume no obligation, and disclaim any duty, to update the forward-looking statements in this report, except as required by law.

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PART I. FINANCIAL INFORMATION
ITEM 1. CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

| For the Three Months |  | For the Nine Months
| Ended September 30, |  | Ended September 30,
| 2019 |  | 2018 |  | 2019 |  | 2018
| (in millions, except per share amounts)
Revenues: |  |  |  |  |  |  |
Electric utility |  | $915.9 |  |  |  | $861.2 |  |  |  | $2,350.5 |  |  |  | $2,296.2 |
Gas utility | 41.5 |  |  | 44.8 |  |  | 322.5 |  |  | 299.0 |
Other utility | 11.2 |  |  | 12.3 |  |  | 33.2 |  |  | 36.2 |
Non-utility | 21.6 |  |  | 10.3 |  |  | 61.4 |  |  | 29.6 |
Total revenues | 990.2 |  |  | 928.6 |  |  | 2,767.6 |  |  | 2,661.0 |
Operating expenses: |  |  |  |  |  |  |
Electric production fuel and purchased power | 218.5 |  |  | 227.8 |  |  | 601.7 |  |  | 639.5 |
Electric transmission service | 127.5 |  |  | 129.1 |  |  | 362.9 |  |  | 375.2 |
Cost of gas sold | 9.1 |  |  | 11.3 |  |  | 151.1 |  |  | 150.0 |
Other operation and maintenance | 173.7 |  |  | 148.4 |  |  | 527.2 |  |  | 468.8 |
Depreciation and amortization | 143.8 |  |  | 129.0 |  |  | 423.6 |  |  | 376.4 |
Taxes other than income taxes | 27.4 |  |  | 26.9 |  |  | 84.3 |  |  | 78.1 |
Total operating expenses | 700.0 |  |  | 672.5 |  |  | 2,150.8 |  |  | 2,088.0 |
Operating income | 290.2 |  |  | 256.1 |  |  | 616.8 |  |  | 573.0 |
Other (income) and deductions: |  |  |  |  |  |  |
Interest expense | 68.3 |  |  | 63.3 |  |  | 203.8 |  |  | 183.8 |
Equity income from unconsolidated investments, net | (11.6 | ) |  | (9.8 | ) |  | (35.2 | ) |  | (41.6 | )
Allowance for funds used during construction | (21.9 | ) |  | (18.8 | ) |  | (65.6 | ) |  | (51.8 | )
Other | 3.7 |  |  | 1.6 |  |  | 11.0 |  |  | 6.0 |
Total other (income) and deductions | 38.5 |  |  | 36.3 |  |  | 114.0 |  |  | 96.4 |
Income before income taxes | 251.7 |  |  | 219.8 |  |  | 502.8 |  |  | 476.6 |
Income taxes | 23.1 |  |  | 11.7 |  |  | 49.4 |  |  | 42.1 |
Net income | 228.6 |  |  | 208.1 |  |  | 453.4 |  |  | 434.5 |
Preferred dividend requirements of Interstate Power and Light Company | 2.6 |  |  | 2.6 |  |  | 7.7 |  |  | 7.7 |
Net income attributable to Alliant Energy common shareowners |  | $226.0 |  |  |  | $205.5 |  |  |  | $445.7 |  |  |  | $426.8 |
Weighted average number of common shares outstanding: |  |  |  |  |  |  |
Basic | 239.1 |  |  | 235.2 |  |  | 237.7 |  |  | 232.9 |
Diluted | 239.9 |  |  | 235.2 |  |  | 238.2 |  |  | 232.9 |
Earnings per weighted average common share attributable to Alliant Energy common shareowners: |  |  |  |  |  |  |
Basic |  | $0.95 |  |  |  | $0.87 |  |  |  | $1.88 |  |  |  | $1.83 |
Diluted |  | $0.94 |  |  |  | $0.87 |  |  |  | $1.87 |  |  |  | $1.83 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

| September 30, 2019 |  | December 31, 2018
| (in millions, except per share and share amounts)
ASSETS |  |  |
Current assets: |  |  |
Cash and cash equivalents |  | $193.7 |  |  |  | $20.9 |
Accounts receivable, less allowance for doubtful accounts | 451.5 |  |  | 350.4 |
Production fuel, at weighted average cost | 71.1 |  |  | 61.4 |
Gas stored underground, at weighted average cost | 46.1 |  |  | 49.0 |
Materials and supplies, at weighted average cost | 106.9 |  |  | 101.4 |
Regulatory assets | 76.3 |  |  | 79.8 |
Prepaid gross receipts tax | 30.3 |  |  | 42.2 |
Other | 137.1 |  |  | 80.0 |
Total current assets | 1,113.0 |  |  | 785.1 |
Property, plant and equipment, net | 13,131.1 |  |  | 12,462.4 |
Investments: |  |  |
ATC Holdings | 309.1 |  |  | 293.6 |
Other | 143.9 |  |  | 137.7 |
Total investments | 453.0 |  |  | 431.3 |
Other assets: |  |  |
Regulatory assets | 1,763.7 |  |  | 1,657.5 |
Deferred charges and other | 72.6 |  |  | 89.7 |
Total other assets | 1,836.3 |  |  | 1,747.2 |
Total assets |  | $16,533.4 |  |  |  | $15,426.0 |

LIABILITIES AND EQUITY |  |  |
Current liabilities: |  |  |
Current maturities of long-term debt |  | $656.8 |  |  |  | $256.5 |
Commercial paper | 349.6 |  |  | 441.2 |
Accounts payable | 497.7 |  |  | 543.3 |
Regulatory liabilities | 188.9 |  |  | 142.7 |
Other | 389.1 |  |  | 260.4 |
Total current liabilities | 2,082.1 |  |  | 1,644.1 |
Long-term debt, net (excluding current portion) | 5,535.1 |  |  | 5,246.3 |
Other liabilities: |  |  |
Deferred tax liabilities | 1,703.0 |  |  | 1,603.1 |
Regulatory liabilities | 1,262.1 |  |  | 1,350.5 |
Pension and other benefit obligations | 476.3 |  |  | 509.1 |
Other | 305.6 |  |  | 287.2 |
Total other liabilities | 3,747.0 |  |  | 3,749.9 |
Commitments and contingencies (Note 14) |  |  |  |  |
Equity: |  |  |
Alliant Energy Corporation common equity: |  |  |
Common stock - $0.01 par value - 480,000,000 shares authorized; 240,342,949 and 236,063,279 shares outstanding | 2.4 |  |  | 2.4 |
Additional paid-in capital | 2,236.9 |  |  | 2,045.5 |
Retained earnings | 2,739.1 |  |  | 2,545.9 |
Accumulated other comprehensive income | 1.0 |  |  | 1.7 |
Shares in deferred compensation trust - 385,343 and 384,580 shares at a weighted average cost of $26.52 and $25.60 per share | (10.2 | ) |  | (9.8 | )
Total Alliant Energy Corporation common equity | 4,969.2 |  |  | 4,585.7 |
Cumulative preferred stock of Interstate Power and Light Company | 200.0 |  |  | 200.0 |
Total equity | 5,169.2 |  |  | 4,785.7 |
Total liabilities and equity |  | $16,533.4 |  |  |  | $15,426.0 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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ALLIANT ENERGY CORPORATION
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

| For the Nine Months
| Ended September 30,
| 2019 |  | 2018
| (in millions)
Cash flows from operating activities: |  |  |
Net income |  | $453.4 |  |  |  | $434.5 |
Adjustments to reconcile net income to net cash flows from operating activities: |  |  |
Depreciation and amortization | 423.6 |  |  | 376.4 |
Deferred tax expense and tax credits | 53.2 |  |  | 62.5 |
Equity component of allowance for funds used during construction | (46.3 | ) |  | (35.5 | )
Other | 17.1 |  |  | 2.1 |
Other changes in assets and liabilities: |  |  |
Accounts receivable | (359.2 | ) |  | (325.2 | )
Accounts payable | (27.9 | ) |  | (47.3 | )
Deferred income taxes | 45.4 |  |  | 32.7 |
Other | (50.1 | ) |  | (58.0 | )
Net cash flows from operating activities | 509.2 |  |  | 442.2 |
Cash flows used for investing activities: |  |  |
Construction and acquisition expenditures: |  |  |
Utility business | (1,003.9 | ) |  | (1,080.2 | )
Other | (71.4 | ) |  | (47.8 | )
Cash receipts on sold receivables | 255.9 |  |  | 337.2 |
Other | (41.7 | ) |  | (24.9 | )
Net cash flows used for investing activities | (861.1 | ) |  | (815.7 | )
Cash flows from financing activities: |  |  |
Common stock dividends | (252.5 | ) |  | (233.3 | )
Proceeds from issuance of common stock, net | 185.4 |  |  | 191.3 |
Proceeds from issuance of long-term debt | 950.0 |  |  | 1,500.0 |
Payments to retire long-term debt | (253.5 | ) |  | (603.1 | )
Net change in commercial paper and other short-term borrowings | (91.6 | ) |  | (278.4 | )
Other | (11.7 | ) |  | 10.9 |
Net cash flows from financing activities | 526.1 |  |  | 587.4 |
Net increase in cash, cash equivalents and restricted cash | 174.2 |  |  | 213.9 |
Cash, cash equivalents and restricted cash at beginning of period | 25.5 |  |  | 33.9 |
Cash, cash equivalents and restricted cash at end of period |  | $199.7 |  |  |  | $247.8 |
Supplemental cash flows information: |  |  |
Cash (paid) refunded during the period for: |  |  |
Interest |  | ($194.7 | ) |  |  | ($171.6 | )
Income taxes, net |  | $0.8 |  |  |  | ($5.0 | )
Significant non-cash investing and financing activities: |  |  |
Accrued capital expenditures |  | $254.2 |  |  |  | $236.2 |
Beneficial interest obtained in exchange for securitized accounts receivable |  | $237.0 |  |  |  | $243.7 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

| For the Three Months |  | For the Nine Months
| Ended September 30, |  | Ended September 30,
| 2019 |  | 2018 |  | 2019 |  | 2018
| (in millions)
Revenues: |  |  |  |  |  |  |
Electric utility |  | $560.9 |  |  |  | $509.2 |  |  |  | $1,373.0 |  |  |  | $1,337.0 |
Gas utility | 24.8 |  |  | 26.7 |  |  | 187.8 |  |  | 177.0 |
Steam and other | 10.8 |  |  | 11.7 |  |  | 32.0 |  |  | 34.2 |
Total revenues | 596.5 |  |  | 547.6 |  |  | 1,592.8 |  |  | 1,548.2 |
Operating expenses: |  |  |  |  |  |  |
Electric production fuel and purchased power | 126.8 |  |  | 122.5 |  |  | 339.0 |  |  | 354.0 |
Electric transmission service | 91.8 |  |  | 92.8 |  |  | 256.9 |  |  | 268.0 |
Cost of gas sold | 5.9 |  |  | 6.4 |  |  | 80.0 |  |  | 83.8 |
Other operation and maintenance | 100.2 |  |  | 94.6 |  |  | 305.6 |  |  | 297.1 |
Depreciation and amortization | 83.7 |  |  | 73.9 |  |  | 243.4 |  |  | 209.2 |
Taxes other than income taxes | 14.6 |  |  | 14.3 |  |  | 46.4 |  |  | 39.7 |
Total operating expenses | 423.0 |  |  | 404.5 |  |  | 1,271.3 |  |  | 1,251.8 |
Operating income | 173.5 |  |  | 143.1 |  |  | 321.5 |  |  | 296.4 |
Other (income) and deductions: |  |  |  |  |  |  |
Interest expense | 31.7 |  |  | 30.4 |  |  | 92.6 |  |  | 90.6 |
Allowance for funds used during construction | (10.8 | ) |  | (11.0 | ) |  | (34.5 | ) |  | (28.3 | )
Other | 2.0 |  |  | 0.5 |  |  | 5.4 |  |  | 2.0 |
Total other (income) and deductions | 22.9 |  |  | 19.9 |  |  | 63.5 |  |  | 64.3 |
Income before income taxes | 150.6 |  |  | 123.2 |  |  | 258.0 |  |  | 232.1 |
Income tax expense (benefit) | 6.9 |  |  | (5.9 | ) |  | 10.9 |  |  | (0.5 | )
Net income | 143.7 |  |  | 129.1 |  |  | 247.1 |  |  | 232.6 |
Preferred dividend requirements | 2.6 |  |  | 2.6 |  |  | 7.7 |  |  | 7.7 |
Earnings available for common stock |  | $141.1 |  |  |  | $126.5 |  |  |  | $239.4 |  |  |  | $224.9 |

Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of IPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

| September 30, 2019 |  | December 31, 2018
| (in millions, except per share and share amounts)
ASSETS |
Current assets: |  |  |
Cash and cash equivalents |  | $184.0 |  |  |  | $9.7 |
Accounts receivable, less allowance for doubtful accounts | 258.3 |  |  | 153.5 |
Production fuel, at weighted average cost | 40.3 |  |  | 44.8 |
Gas stored underground, at weighted average cost | 21.6 |  |  | 26.1 |
Materials and supplies, at weighted average cost | 60.3 |  |  | 55.4 |
Regulatory assets | 34.6 |  |  | 39.2 |
Other | 22.1 |  |  | 43.1 |
Total current assets | 621.2 |  |  | 371.8 |
Property, plant and equipment, net | 7,283.9 |  |  | 6,781.5 |
Other assets: |  |  |
Regulatory assets | 1,369.4 |  |  | 1,239.8 |
Deferred charges and other | 28.1 |  |  | 18.3 |
Total other assets | 1,397.5 |  |  | 1,258.1 |
Total assets |  | $9,302.6 |  |  |  | $8,411.4 |

LIABILITIES AND EQUITY |
Current liabilities: |  |  |
Current maturities of long-term debt |  | $200.0 |  |  |  | $— |
Commercial paper | — |  |  | 50.4 |
Accounts payable | 290.0 |  |  | 304.9 |
Accounts payable to associated companies | 40.7 |  |  | 28.8 |
Regulatory liabilities | 95.5 |  |  | 90.0 |
Accrued taxes | 58.7 |  |  | 45.8 |
Other | 197.7 |  |  | 87.2 |
Total current liabilities | 882.6 |  |  | 607.1 |
Long-term debt, net (excluding current portion) | 2,946.8 |  |  | 2,552.3 |
Other liabilities: |  |  |
Deferred tax liabilities | 974.9 |  |  | 957.3 |
Regulatory liabilities | 638.1 |  |  | 664.9 |
Pension and other benefit obligations | 165.1 |  |  | 178.4 |
Other | 251.0 |  |  | 220.7 |
Total other liabilities | 2,029.1 |  |  | 2,021.3 |
Commitments and contingencies (Note 14) |  |  |  |  |
Equity: |  |  |
Interstate Power and Light Company common equity: |  |  |
Common stock - $2.50 par value - 24,000,000 shares authorized; 13,370,788 shares outstanding | 33.4 |  |  | 33.4 |
Additional paid-in capital | 2,322.8 |  |  | 2,222.8 |
Retained earnings | 887.9 |  |  | 774.5 |
Total Interstate Power and Light Company common equity | 3,244.1 |  |  | 3,030.7 |
Cumulative preferred stock | 200.0 |  |  | 200.0 |
Total equity | 3,444.1 |  |  | 3,230.7 |
Total liabilities and equity |  | $9,302.6 |  |  |  | $8,411.4 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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INTERSTATE POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

| For the Nine Months
| Ended September 30,
| 2019 |  | 2018
| (in millions)
Cash flows from operating activities: |  |  |
Net income |  | $247.1 |  |  |  | $232.6 |
Adjustments to reconcile net income to net cash flows from operating activities: |  |  |
Depreciation and amortization | 243.4 |  |  | 209.2 |
Equity component of allowance for funds used during construction | (24.6 | ) |  | (19.3 | )
Other | (13.2 | ) |  | 0.7 |
Other changes in assets and liabilities: |  |  |
Accounts receivable | (365.0 | ) |  | (353.2 | )
Accounts payable | (14.0 | ) |  | (34.5 | )
Deferred income taxes | 31.5 |  |  | 22.9 |
Other | 33.3 |  |  | (19.5 | )
Net cash flows from operating activities | 138.5 |  |  | 38.9 |
Cash flows used for investing activities: |  |  |
Construction and acquisition expenditures | (696.3 | ) |  | (635.2 | )
Cash receipts on sold receivables | 255.9 |  |  | 337.2 |
Other | (43.7 | ) |  | (30.9 | )
Net cash flows used for investing activities | (484.1 | ) |  | (328.9 | )
Cash flows from financing activities: |  |  |
Common stock dividends | (126.0 | ) |  | (125.9 | )
Capital contributions from parent | 100.0 |  |  | 230.0 |
Proceeds from issuance of long-term debt | 600.0 |  |  | 500.0 |
Payments to retire long-term debt | — |  |  | (100.0 | )
Net change in commercial paper | (50.4 | ) |  | — |
Other | (5.1 | ) |  | 15.0 |
Net cash flows from financing activities | 518.5 |  |  | 519.1 |
Net increase in cash, cash equivalents and restricted cash | 172.9 |  |  | 229.1 |
Cash, cash equivalents and restricted cash at beginning of period | 12.4 |  |  | 7.2 |
Cash, cash equivalents and restricted cash at end of period |  | $185.3 |  |  |  | $236.3 |
Supplemental cash flows information: |  |  |
Cash (paid) refunded during the period for: |  |  |
Interest |  | ($93.9 | ) |  |  | ($89.1 | )
Income taxes, net |  | $8.2 |  |  |  | ($2.4 | )
Significant non-cash investing and financing activities: |  |  |
Accrued capital expenditures |  | $180.2 |  |  |  | $142.4 |
Beneficial interest obtained in exchange for securitized accounts receivable |  | $237.0 |  |  |  | $243.7 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)

| For the Three Months |  | For the Nine Months
| Ended September 30, |  | Ended September 30,
| 2019 |  | 2018 |  | 2019 |  | 2018
| (in millions)
Revenues: |  |  |  |  |  |  |
Electric utility |  | $355.0 |  |  |  | $352.0 |  |  |  | $977.5 |  |  |  | $959.2 |
Gas utility | 16.7 |  |  | 18.1 |  |  | 134.7 |  |  | 122.0 |
Other | 0.4 |  |  | 0.6 |  |  | 1.2 |  |  | 2.0 |
Total revenues | 372.1 |  |  | 370.7 |  |  | 1,113.4 |  |  | 1,083.2 |
Operating expenses: |  |  |  |  |  |  |
Electric production fuel and purchased power | 91.7 |  |  | 105.3 |  |  | 262.7 |  |  | 285.5 |
Electric transmission service | 35.7 |  |  | 36.3 |  |  | 106.0 |  |  | 107.2 |
Cost of gas sold | 3.2 |  |  | 4.9 |  |  | 71.1 |  |  | 66.2 |
Other operation and maintenance | 62.3 |  |  | 54.2 |  |  | 188.2 |  |  | 172.8 |
Depreciation and amortization | 58.9 |  |  | 54.1 |  |  | 176.6 |  |  | 164.2 |
Taxes other than income taxes | 12.0 |  |  | 11.7 |  |  | 35.4 |  |  | 35.7 |
Total operating expenses | 263.8 |  |  | 266.5 |  |  | 840.0 |  |  | 831.6 |
Operating income | 108.3 |  |  | 104.2 |  |  | 273.4 |  |  | 251.6 |
Other (income) and deductions: |  |  |  |  |  |  |
Interest expense | 25.4 |  |  | 24.2 |  |  | 77.3 |  |  | 73.5 |
Allowance for funds used during construction | (11.1 | ) |  | (7.8 | ) |  | (31.1 | ) |  | (23.5 | )
Other | 1.4 |  |  | 1.3 |  |  | 4.6 |  |  | 3.4 |
Total other (income) and deductions | 15.7 |  |  | 17.7 |  |  | 50.8 |  |  | 53.4 |
Income before income taxes | 92.6 |  |  | 86.5 |  |  | 222.6 |  |  | 198.2 |
Income taxes | 17.1 |  |  | 10.2 |  |  | 39.4 |  |  | 28.1 |
Earnings available for common stock |  | $75.5 |  |  |  | $76.3 |  |  |  | $183.2 |  |  |  | $170.1 |

Earnings per share data is not disclosed given Alliant Energy Corporation is the sole shareowner of all shares of WPL’s common stock outstanding during the periods presented.
Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED BALANCE SHEETS (UNAUDITED)

| September 30, 2019 |  | December 31, 2018
| (in millions, except per share and share amounts)
ASSETS |
Current assets: |  |  |
Cash and cash equivalents |  | $8.3 |  |  |  | $8.7 |
Accounts receivable, less allowance for doubtful accounts | 184.3 |  |  | 190.1 |
Production fuel, at weighted average cost | 30.8 |  |  | 16.6 |
Gas stored underground, at weighted average cost | 24.5 |  |  | 22.9 |
Materials and supplies, at weighted average cost | 43.7 |  |  | 42.9 |
Regulatory assets | 41.7 |  |  | 40.6 |
Prepaid gross receipts tax | 30.3 |  |  | 42.2 |
Other | 86.6 |  |  | 20.6 |
Total current assets | 450.2 |  |  | 384.6 |
Property, plant and equipment, net | 5,449.7 |  |  | 5,287.3 |
Other assets: |  |  |
Regulatory assets | 394.3 |  |  | 417.7 |
Deferred charges and other | 19.5 |  |  | 62.9 |
Total other assets | 413.8 |  |  | 480.6 |
Total assets |  | $6,313.7 |  |  |  | $6,152.5 |

LIABILITIES AND EQUITY |
Current liabilities: |  |  |
Current maturities of long-term debt |  | $150.0 |  |  |  | $250.0 |
Commercial paper | — |  |  | 105.5 |
Accounts payable | 151.1 |  |  | 180.9 |
Regulatory liabilities | 93.4 |  |  | 52.7 |
Other | 113.6 |  |  | 105.5 |
Total current liabilities | 508.1 |  |  | 694.6 |
Long-term debt, net (excluding current portion) | 1,782.3 |  |  | 1,584.9 |
Other liabilities: |  |  |
Deferred tax liabilities | 652.6 |  |  | 582.0 |
Regulatory liabilities | 624.0 |  |  | 685.6 |
Finance lease obligations - Sheboygan Falls Energy Facility | 53.6 |  |  | 60.0 |
Pension and other benefit obligations | 203.5 |  |  | 217.7 |
Other | 164.8 |  |  | 178.2 |
Total other liabilities | 1,698.5 |  |  | 1,723.5 |
Commitments and contingencies (Note 14) |  |  |
Equity: |  |  |
Wisconsin Power and Light Company common equity: |  |  |
Common stock - $5 par value - 18,000,000 shares authorized; 13,236,601 shares outstanding | 66.2 |  |  | 66.2 |
Additional paid-in capital | 1,409.0 |  |  | 1,309.0 |
Retained earnings | 849.6 |  |  | 774.3 |
Total Wisconsin Power and Light Company common equity | 2,324.8 |  |  | 2,149.5 |
Total liabilities and equity |  | $6,313.7 |  |  |  | $6,152.5 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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WISCONSIN POWER AND LIGHT COMPANY
CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED)

| For the Nine Months
| Ended September 30,
| 2019 |  | 2018
| (in millions)
Cash flows from operating activities: |  |  |
Net income |  | $183.2 |  |  |  | $170.1 |
Adjustments to reconcile net income to net cash flows from operating activities: |  |  |
Depreciation and amortization | 176.6 |  |  | 164.2 |
Deferred tax expense and tax credits | 54.6 |  |  | 50.3 |
Other | (7.8 | ) |  | (12.0 | )
Other changes in assets and liabilities: |  |  |
Accounts receivable | 3.8 |  |  | 29.7 |
Regulatory liabilities | (28.6 | ) |  | 7.2 |
Other | (22.2 | ) |  | (64.0 | )
Net cash flows from operating activities | 359.6 |  |  | 345.5 |
Cash flows used for investing activities: |  |  |
Construction and acquisition expenditures | (307.6 | ) |  | (445.0 | )
Other | (27.3 | ) |  | (23.7 | )
Net cash flows used for investing activities | (334.9 | ) |  | (468.7 | )
Cash flows from (used for) financing activities: |  |  |
Common stock dividends | (107.9 | ) |  | (105.0 | )
Capital contributions from parent | 100.0 |  |  | 200.0 |
Proceeds from issuance of long-term debt | 350.0 |  |  | — |
Payments to retire long-term debt | (250.0 | ) |  | — |
Net change in commercial paper | (105.5 | ) |  | 13.4 |
Other | (10.9 | ) |  | (1.7 | )
Net cash flows from (used for) financing activities | (24.3 | ) |  | 106.7 |
Net increase (decrease) in cash, cash equivalents and restricted cash | 0.4 |  |  | (16.5 | )
Cash, cash equivalents and restricted cash at beginning of period | 9.2 |  |  | 24.2 |
Cash, cash equivalents and restricted cash at end of period |  | $9.6 |  |  |  | $7.7 |
Supplemental cash flows information: |  |  |
Cash paid during the period for: |  |  |
Interest |  | ($73.9 | ) |  |  | ($68.5 | )
Income taxes, net |  | ($7.0 | ) |  |  | ($11.2 | )
Significant non-cash investing and financing activities: |  |  |
Accrued capital expenditures |  | $70.3 |  |  |  | $86.2 |

Refer to accompanying Combined Notes to Condensed Consolidated Financial Statements.

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ALLIANT ENERGY CORPORATION
INTERSTATE POWER AND LIGHT COMPANY
WISCONSIN POWER AND LIGHT COMPANY
COMBINED NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (UNAUDITED)
NOTE 1. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K.
In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the nine months ended September 30, 2019 are not necessarily indicative of results that may be expected for the year ending December 31, 2019. A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes.
NOTE 1(b) Cash and Cash Equivalents - At September 30, 2019, Alliant Energy’s and IPL’s cash and cash equivalents included $174.4 million and $173.7 million of money market fund investments, with interest rates of 2.0% and 2.0%, respectively.
NOTE 1(c) Leases - The determination of whether an arrangement qualifies as a lease occurs at the inception of the arrangement. Arrangements that qualify as leases are classified as either operating or finance. Operating and finance lease liabilities represent obligations to make payments arising from the lease. Operating and finance lease assets represent the right to use an underlying asset for the lease term and are recognized at the lease commencement date based on the present value of the lease payments over the lease term. Leases with initial terms less than 12 months are not recognized as leases. For operating leases, an incremental borrowing rate, as determined at the lease commencement date, is used to determine the present value of the lease payments. For finance leases, the rate implicit in the lease is used to determine the present value of the lease payments. Lease terms include options to extend or terminate the lease when it is reasonably certain that the option will be exercised. Operating lease expense is recognized on a straight-line basis over the expected lease term. Finance lease expense is comprised of depreciation and interest expenses. Finance lease assets are depreciated on a straight-line basis over the shorter of the useful life of the underlying asset or the lease term.
NOTE 1(d) New Accounting Standards -
Credit Losses - In June 2016, the Financial Accounting Standards Board issued an accounting standard requiring use of a current expected credit loss model rather than an incurred loss method, which is intended to result in more timely recognition of credit losses on trade receivables and certain other assets. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2020 using the modified retrospective method of adoption, which requires cumulative effect adjustments to retained earnings on January 1, 2020 upon adoption. Alliant Energy, IPL and WPL will continue to evaluate the impact of this standard and do not currently expect a material change to their financial condition or results of operations as a result of adopting this standard.
Cloud Computing Arrangements - In August 2018, the Financial Accounting Standards Board issued an accounting standard that clarifies capitalization and presentation requirements of implementation costs incurred in cloud computing arrangements. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2020 and are currently evaluating the impact of this standard on their financial statements.

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Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet. The accounting for capital leases, now referred to as finance leases, remains unchanged with the adoption of this standard. Alliant Energy, IPL and WPL adopted this standard on January 1, 2019 using an optional transition approach and there was no cumulative effect adjustment to the balance sheets as of January 1, 2019. Prior period amounts have not been restated to reflect the adoption of this standard and continue to be reported under the accounting standards in effect for those periods. Upon transition to the new standard, Alliant Energy, IPL and WPL elected the land easement transition practical expedient, for which existing land easements that were not previously accounted for as leases under the original accounting standards did not need to be evaluated under the new accounting standard. In addition, Alliant Energy, IPL and WPL evaluated land easements that were previously accounted for as leases and determined that the majority of these land easements relate to joint-use land sites, and do not meet the criteria for leases under the new accounting standard. Therefore, these land easement arrangements are no longer reflected as operating leases effective January 1, 2019. Refer to Note 7 for further discussion of leases.
NOTE 2. REGULATORY MATTERS
Regulatory Assets and Regulatory Liabilities -
Regulatory assets were comprised of the following items (in millions):

| Alliant Energy |  | IPL |  | WPL
| September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018
Tax-related |  | $825.2 |  |  |  | $820.6 |  |  |  | $787.2 |  |  |  | $783.1 |  |  |  | $38.0 |  |  |  | $37.5 |
Pension and OPEB costs | 513.1 |  |  | 542.3 |  |  | 260.0 |  |  | 274.0 |  |  | 253.1 |  |  | 268.3 |
Assets retired early | 138.7 |  |  | 111.6 |  |  | 90.1 |  |  | 55.4 |  |  | 48.6 |  |  | 56.2 |
Asset retirement obligations | 110.7 |  |  | 110.8 |  |  | 75.2 |  |  | 76.3 |  |  | 35.5 |  |  | 34.5 |
IPL’s DAEC PPA amendment | 107.7 |  |  | — |  |  | 107.7 |  |  | — |  |  | — |  |  | — |
Derivatives | 34.0 |  |  | 28.0 |  |  | 15.0 |  |  | 15.1 |  |  | 19.0 |  |  | 12.9 |
Emission allowances | 21.7 |  |  | 23.6 |  |  | 21.7 |  |  | 23.6 |  |  | — |  |  | — |
Other | 88.9 |  |  | 100.4 |  |  | 47.1 |  |  | 51.5 |  |  | 41.8 |  |  | 48.9 |
|  | $1,840.0 |  |  |  | $1,737.3 |  |  |  | $1,404.0 |  |  |  | $1,279.0 |  |  |  | $436.0 |  |  |  | $458.3 |

Regulatory liabilities were comprised of the following items (in millions):

| Alliant Energy |  | IPL |  | WPL
| September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018
Tax-related |  | $851.4 |  |  |  | $890.6 |  |  |  | $365.0 |  |  |  | $390.1 |  |  |  | $486.4 |  |  |  | $500.5 |
Cost of removal obligations | 390.9 |  |  | 401.2 |  |  | 261.0 |  |  | 273.3 |  |  | 129.9 |  |  | 127.9 |
Electric transmission cost recovery | 89.8 |  |  | 104.0 |  |  | 48.0 |  |  | 47.7 |  |  | 41.8 |  |  | 56.3 |
Commodity cost recovery | 29.1 |  |  | 16.8 |  |  | 16.7 |  |  | 11.9 |  |  | 12.4 |  |  | 4.9 |
WPL’s earnings sharing mechanism | 21.8 |  |  | 25.4 |  |  | — |  |  | — |  |  | 21.8 |  |  | 25.4 |
Derivatives | 20.8 |  |  | 18.5 |  |  | 16.9 |  |  | 10.2 |  |  | 3.9 |  |  | 8.3 |
Other | 47.2 |  |  | 36.7 |  |  | 26.0 |  |  | 21.7 |  |  | 21.2 |  |  | 15.0 |
|  | $1,451.0 |  |  |  | $1,493.2 |  |  |  | $733.6 |  |  |  | $754.9 |  |  |  | $717.4 |  |  |  | $738.3 |

Assets Retired Early - Upon completion of the phased installation of advanced metering infrastructure, IPL retired certain analog electric meters in September 2019 and reclassified the $36 million remaining net book value of these meters from property, plant and equipment to a regulatory asset on Alliant Energy’s and IPL’s balance sheets. Recovery of these retired meters is included in the settlement agreement for IPL’s current retail electric base rate increase, and the IUB will decide on the recovery of these assets with the current retail electric rate review decision.
IPL’s DAEC PPA Amendment - In January 2019, IPL incurred an obligation to make a September 2020 buyout payment of $110 million in exchange for shortening the term of IPL’s DAEC nuclear generation PPA by 5 years. The IUB approved placing the buyout payment in a regulatory asset account, which will be recovered from IPL’s retail customers over a 5-year period following the payment. The offsetting obligation has been discounted and is recorded in “Other current liabilities” on Alliant Energy’s and IPL’s balance sheets.

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Utility Rate Reviews
IPL’s Retail Electric Rate Review (2020 Forward-looking Test Period) - In March 2019, IPL filed a request with the IUB to increase annual electric base rates for its Iowa retail electric customers based on a 2020 forward-looking Test Period. The key drivers for IPL’s request included recovery of capital projects, including new wind generation. IPL concurrently filed for interim retail electric rates based on 2018 historical data as adjusted for certain known and measurable changes occurring in the first quarter of 2019. An interim retail electric base rate increase of $90 million, on an annual basis, was implemented effective April 1, 2019. Implementing interim rates does not require regulatory approval; however, interim rates are subject to refund pending the IUB’s final rate review decision.
In October 2019, IPL reached a partial, non-unanimous settlement agreement with intervenor groups for an annual retail electric base rate increase of $127 million. The agreement includes both the recovery of and a return on IPL’s early retired EGUs, and the recovery of IPL’s retired analog electric meters. The settlement agreement also includes IPL providing billing credits over a 12-month period beginning with final rates, including $27 million of excess deferred taxes resulting from the remeasurement of accumulated deferred income taxes caused by Federal Tax Reform and $8 million from a partial refund of interim rates implemented in 2019.
The IUB generally must decide on requests for retail rate changes within 10 months of the date of the application for which changes are filed. IPL currently expects a final decision, including a decision on the settlement agreement, from the IUB in the fourth quarter of 2019 with final rates effective in the first quarter of 2020.
IPL’s Retail Gas Rate Review (2020 Forward-looking Test Period) - In March 2019, IPL filed a request with the IUB to increase annual gas base rates for its Iowa retail gas customers based on a 2020 forward-looking Test Period. The key drivers for IPL’s request included recovery of capital projects. In October 2019, IPL reached a unanimous settlement agreement with intervenor groups for an annual retail gas base rate increase of $12 million. IPL currently expects a decision, including a decision on the settlement agreement, from the IUB in the fourth quarter of 2019 with final rates effective in the first quarter of 2020.
NOTE 3. RECEIVABLES
Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of September 30, 2019, IPL had $109 million of available capacity under its sales of accounts receivable program. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three and nine months ended September 30 were as follows (in millions):

| Three Months |  | Nine Months
| 2019 |  | 2018 |  | 2019 |  | 2018
Maximum outstanding aggregate cash proceeds |  | $103.0 |  |  |  | $110.0 |  |  |  | $108.0 |  |  |  | $116.0 |
Average outstanding aggregate cash proceeds | 45.4 |  |  | 36.4 |  |  | 42.9 |  |  | 49.8 |

The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions):

| September 30, 2019 |  | December 31, 2018
Customer accounts receivable |  | $154.2 |  |  |  | $140.1 |
Unbilled utility revenues | 92.1 |  |  | 97.1 |
Other receivables | 0.4 |  |  | 0.1 |
Receivables sold to third party | 246.7 |  |  | 237.3 |
Less: cash proceeds | 1.0 |  |  | 108.0 |
Deferred proceeds | 245.7 |  |  | 129.3 |
Less: allowance for doubtful accounts | 8.7 |  |  | 9.9 |
Fair value of deferred proceeds |  | $237.0 |  |  |  | $119.4 |

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As of September 30, 2019, outstanding receivables past due under the Receivables Agreement were $26.6 million. Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three and nine months ended September 30 were as follows (in millions):

| Three Months |  | Nine Months
| 2019 |  | 2018 |  | 2019 |  | 2018
Collections |  | $592.2 |  |  |  | $549.5 |  |  |  | $1,635.7 |  |  |  | $1,550.2 |
Write-offs, net of recoveries | 3.2 |  |  | 4.9 |  |  | 11.3 |  |  | 12.9 |

NOTE 4. INVESTMENTS AND ACQUISITIONS
Unconsolidated Equity Investments - Alliant Energy’s equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three and nine months ended September 30 was as follows (in millions):

| Three Months |  | Nine Months
| 2019 |  | 2018 |  | 2019 |  | 2018
ATC Holdings |  | ($10.5 | ) |  |  | ($8.9 | ) |  |  | ($30.0 | ) |  |  | ($25.4 | )
Non-utility wind farm in Oklahoma | (0.4 | ) |  | 0.1 |  |  | (2.8 | ) |  | (14.5 | )
Other | (0.7 | ) |  | (1.0 | ) |  | (2.4 | ) |  | (1.7 | )
|  | ($11.6 | ) |  |  | ($9.8 | ) |  |  | ($35.2 | ) |  |  | ($41.6 | )

Non-utility Transportation Acquisitions - In the first quarter of 2019, Alliant Energy, through its wholly-owned non-utility subsidiaries, completed acquisitions of freight management companies located in Cedar Rapids, Iowa and Stoughton, Wisconsin. These acquisitions were purchased for $21 million, including contingent consideration of $8 million, which is expected to be paid within two years. The purchase price was largely allocated to intangibles and the remainder was allocated to working capital and property.
NOTE 5. COMMON EQUITY
Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows:

Shares outstanding, January 1, 2019 | 236,063,279 |
Equity forward agreements | 3,790,300 |
Shareowner Direct Plan | 390,630 |
Equity-based compensation plans | 101,478 |
Other | (2,738 | )
Shares outstanding, September 30, 2019 | 240,342,949 |

Equity Forward Agreements - In December 2018, Alliant Energy entered into forward sale agreements with various counterparties in connection with a public offering of 8,358,973 shares of Alliant Energy common stock. The initial forward sale price of $44.33 per share is subject to daily adjustment based on a floating interest rate factor, and will decrease by other fixed amounts specified in the forward sale agreements. In 2019, Alliant Energy settled $167 million under the forward sale agreements by delivering 3,790,300 shares of newly issued Alliant Energy common stock at a weighted average forward sale price of $43.99 per share. Alliant Energy used the net proceeds from the settlements for general corporate purposes. As of September 30, 2019, 671,237 incremental shares were included in the calculation of diluted EPS related to the remaining securities under the forward sale agreements.

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Changes in Shareowners’ Equity - A summary of changes in shareowners’ equity was as follows (in millions):

Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, July 1 |  | $2.4 |  |  |  | $2,108.4 |  |  |  | $2,597.8 |  |  |  | $1.0 |  |  |  | ($10.0 | ) |  |  | $200.0 |  |  |  | $4,899.6 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 226.0 |  |  |  |  |  |  |  |  | 226.0 |
Common stock dividends ($0.355 per share) |  |  |  |  | (84.7 | ) |  |  |  |  |  |  |  | (84.7 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 124.8 |  |  |  |  |  |  |  |  |  |  | 124.8 |
Equity-based compensation plans and other |  |  | 3.7 |  |  |  |  |  |  | (0.2 | ) |  |  |  | 3.5 |
Ending balance, September 30 |  | $2.4 |  |  |  | $2,236.9 |  |  |  | $2,739.1 |  |  |  | $1.0 |  |  |  | ($10.2 | ) |  |  | $200.0 |  |  |  | $5,169.2 |
Three Months Ended September 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, July 1 |  | $2.3 |  |  |  | $1,947.2 |  |  |  | $2,412.5 |  |  |  | $0.1 |  |  |  | ($11.4 | ) |  |  | $200.0 |  |  |  | $4,550.7 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 205.5 |  |  |  |  |  |  |  |  | 205.5 |
Common stock dividends ($0.335 per share) |  |  |  |  | (78.5 | ) |  |  |  |  |  |  |  | (78.5 | )
At-the-market offering program and Shareowner Direct Plan issuances | 0.1 |  |  | 91.1 |  |  |  |  |  |  |  |  |  |  | 91.2 |
Equity-based compensation plans and other |  |  | (0.1 | ) |  |  |  |  |  | 1.9 |  |  |  |  | 1.8 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (0.3 | ) |  |  |  |  |  | (0.3 | )
Ending balance, September 30 |  | $2.4 |  |  |  | $2,038.2 |  |  |  | $2,539.5 |  |  |  | ($0.2 | ) |  |  | ($9.5 | ) |  |  | $200.0 |  |  |  | $4,770.4 |

Alliant Energy | Total Alliant Energy Common Equity |  |  |  |
|  |  |  |  |  |  | Accumulated |  | Shares in |  | Cumulative |  |
|  |  | Additional |  |  |  | Other |  | Deferred |  | Preferred |  |
| Common |  | Paid-In |  | Retained |  | Comprehensive |  | Compensation |  | Stock |  | Total
| Stock |  | Capital |  | Earnings |  | Income (Loss) |  | Trust |  | of IPL |  | Equity
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.4 |  |  |  | $2,045.5 |  |  |  | $2,545.9 |  |  |  | $1.7 |  |  |  | ($9.8 | ) |  |  | $200.0 |  |  |  | $4,785.7 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 445.7 |  |  |  |  |  |  |  |  | 445.7 |
Common stock dividends ($1.065 per share) |  |  |  |  | (252.5 | ) |  |  |  |  |  |  |  | (252.5 | )
Equity forward settlements and Shareowner Direct Plan issuances |  |  |  | 185.4 |  |  |  |  |  |  |  |  |  |  | 185.4 |
Equity-based compensation plans and other |  |  | 6.0 |  |  |  |  |  |  | (0.4 | ) |  |  |  | 5.6 |
Other comprehensive loss, net of tax |  |  |  |  |  |  | (0.7 | ) |  |  |  |  |  | (0.7 | )
Ending balance, September 30 |  | $2.4 |  |  |  | $2,236.9 |  |  |  | $2,739.1 |  |  |  | $1.0 |  |  |  | ($10.2 | ) |  |  | $200.0 |  |  |  | $5,169.2 |
Nine Months Ended September 30, 2018 |  |  |  |  |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $2.3 |  |  |  | $1,845.5 |  |  |  | $2,346.0 |  |  |  | ($0.5 | ) |  |  | ($11.1 | ) |  |  | $200.0 |  |  |  | $4,382.2 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  | 426.8 |  |  |  |  |  |  |  |  | 426.8 |
Common stock dividends ($1.005 per share) |  |  |  |  | (233.3 | ) |  |  |  |  |  |  |  | (233.3 | )
At-the-market offering program and Shareowner Direct Plan issuances | 0.1 |  |  | 191.2 |  |  |  |  |  |  |  |  |  |  | 191.3 |
Equity-based compensation plans and other |  |  | 1.5 |  |  |  |  |  |  | 1.6 |  |  |  |  | 3.1 |
Other comprehensive income, net of tax |  |  |  |  |  |  | 0.3 |  |  |  |  |  |  | 0.3 |
Ending balance, September 30 |  | $2.4 |  |  |  | $2,038.2 |  |  |  | $2,539.5 |  |  |  | ($0.2 | ) |  |  | ($9.5 | ) |  |  | $200.0 |  |  |  | $4,770.4 |

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IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, July 1 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $788.9 |  |  |  | $200.0 |  |  |  | $3,345.1 |
Earnings available for common stock |  |  |  |  | 141.1 |  |  |  |  | 141.1 |
Common stock dividends |  |  |  |  | (42.1 | ) |  |  |  | (42.1 | )
Ending balance, September 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $887.9 |  |  |  | $200.0 |  |  |  | $3,444.1 |
Three Months Ended September 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, July 1 |  | $33.4 |  |  |  | $1,927.8 |  |  |  | $692.9 |  |  |  | $200.0 |  |  |  | $2,854.1 |
Earnings available for common stock |  |  |  |  | 126.5 |  |  |  |  | 126.5 |
Common stock dividends |  |  |  |  | (41.9 | ) |  |  |  | (41.9 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  |  |  | 100.0 |
Ending balance, September 30 |  | $33.4 |  |  |  | $2,027.8 |  |  |  | $777.5 |  |  |  | $200.0 |  |  |  | $3,038.7 |

IPL | Total IPL Common Equity |  |  |  |
|  |  | Additional |  |  |  | Cumulative |  |
| Common |  | Paid-In |  | Retained |  | Preferred |  | Total
| Stock |  | Capital |  | Earnings |  | Stock |  | Equity
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $2,222.8 |  |  |  | $774.5 |  |  |  | $200.0 |  |  |  | $3,230.7 |
Earnings available for common stock |  |  |  |  | 239.4 |  |  |  |  | 239.4 |
Common stock dividends |  |  |  |  | (126.0 | ) |  |  |  | (126.0 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  |  |  | 100.0 |
Ending balance, September 30 |  | $33.4 |  |  |  | $2,322.8 |  |  |  | $887.9 |  |  |  | $200.0 |  |  |  | $3,444.1 |
Nine Months Ended September 30, 2018 |  |  |  |  |  |  |  |  |
Beginning balance, January 1 |  | $33.4 |  |  |  | $1,797.8 |  |  |  | $678.5 |  |  |  | $200.0 |  |  |  | $2,709.7 |
Earnings available for common stock |  |  |  |  | 224.9 |  |  |  |  | 224.9 |
Common stock dividends |  |  |  |  | (125.9 | ) |  |  |  | (125.9 | )
Capital contributions from parent |  |  | 230.0 |  |  |  |  |  |  | 230.0 |
Ending balance, September 30 |  | $33.4 |  |  |  | $2,027.8 |  |  |  | $777.5 |  |  |  | $200.0 |  |  |  | $3,038.7 |

WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, July 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $810.0 |  |  |  | $2,185.2 |
Earnings available for common stock |  |  |  |  | 75.5 |  |  | 75.5 |
Common stock dividends |  |  |  |  | (35.9 | ) |  | (35.9 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  | 100.0 |
Ending balance, September 30 |  | $66.2 |  |  |  | $1,409.0 |  |  |  | $849.6 |  |  |  | $2,324.8 |
Three Months Ended September 30, 2018 |  |  |  |  |  |  |
Beginning balance, July 1 |  | $66.2 |  |  |  | $1,259.0 |  |  |  | $730.0 |  |  |  | $2,055.2 |
Earnings available for common stock |  |  |  |  | 76.3 |  |  | 76.3 |
Common stock dividends |  |  |  |  | (34.9 | ) |  | (34.9 | )
Capital contributions from parent |  |  | 50.0 |  |  |  |  | 50.0 |
Ending balance, September 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $771.4 |  |  |  | $2,146.6 |

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WPL |  |  | Additional |  |  |  | Total
| Common |  | Paid-In |  | Retained |  | Common
| Stock |  | Capital |  | Earnings |  | Equity
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $774.3 |  |  |  | $2,149.5 |
Earnings available for common stock |  |  |  |  | 183.2 |  |  | 183.2 |
Common stock dividends |  |  |  |  | (107.9 | ) |  | (107.9 | )
Capital contributions from parent |  |  | 100.0 |  |  |  |  | 100.0 |
Ending balance, September 30 |  | $66.2 |  |  |  | $1,409.0 |  |  |  | $849.6 |  |  |  | $2,324.8 |
Nine Months Ended September 30, 2018 |  |  |  |  |  |  |
Beginning balance, January 1 |  | $66.2 |  |  |  | $1,109.0 |  |  |  | $706.3 |  |  |  | $1,881.5 |
Earnings available for common stock |  |  |  |  | 170.1 |  |  | 170.1 |
Common stock dividends |  |  |  |  | (105.0 | ) |  | (105.0 | )
Capital contributions from parent |  |  | 200.0 |  |  |  |  | 200.0 |
Ending balance, September 30 |  | $66.2 |  |  |  | $1,309.0 |  |  |  | $771.4 |  |  |  | $2,146.6 |

Comprehensive Income - For the three and nine months ended September 30, 2019 and 2018, Alliant Energy’s other comprehensive income was not material; therefore, its comprehensive income was substantially equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was substantially equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three and nine months ended September 30, 2019 and 2018, IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods.
NOTE 6. DEBT
NOTE 6(a) Short-term Debt - In March 2019, Alliant Energy, IPL and WPL extended their single credit facility agreement by one year, which currently expires in August 2023. As of September 30, 2019, the short-term borrowing capacity under the agreement totaled $1 billion ($450 million for Alliant Energy at the parent company, $250 million for IPL and $300 million for WPL). Information regarding commercial paper classified as short-term debt was as follows (dollars in millions):

September 30, 2019 | Alliant Energy |  | IPL |  | WPL
Commercial paper outstanding | $349.6 |  | $— |  | $—
Commercial paper weighted average interest rates | 2.3% |  | N/A |  | N/A
Available credit facility capacity | $650.4 |  | $250.0 |  | $300.0

| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Maximum amount outstanding (based on daily outstanding balances) | $471.7 |  | $153.3 |  | $— |  | $— |  | $89.7 |  | $75.4
Average amount outstanding (based on daily outstanding balances) | $399.5 |  | $80.8 |  | $— |  | $— |  | $27.0 |  | $23.1
Weighted average interest rates | 2.5% |  | 2.2% |  | N/A |  | N/A |  | 2.3% |  | 2.0%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $600.6 |  | $446.5 |  | $50.4 |  | $31.4 |  | $195.1 |  | $109.4
Average amount outstanding (based on daily outstanding balances) | $476.3 |  | $207.6 |  | $0.2 |  | $1.7 |  | $101.8 |  | $26.6
Weighted average interest rates | 2.6% |  | 2.1% |  | 2.8% |  | 2.3% |  | 2.5% |  | 1.9%

NOTE 6(b) Long-term Debt - In April 2019, IPL issued $300 million of 3.60% senior debentures due 2029. In September 2019, IPL issued $300 million of 3.50% senior debentures due 2049. The senior debentures were issued as green bonds, and all of the net proceeds have been or will be allocated for the construction and development of IPL’s wind projects.
In June 2019, WPL issued $350 million of 3.00% debentures due 2029. The net proceeds from the issuance were used by WPL to reduce its outstanding commercial paper and retire its $250 million 5% debentures that matured in July 2019.

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NOTE 7. LEASES
Operating Leases - Alliant Energy’s, IPL’s and WPL’s operating leases primarily include leases of space on telecommunication towers and leases of property. Operating lease details are as follows (dollars in millions):

| September 30, 2019 |  |  |  |  |  |
| Alliant Energy |  | IPL |  | WPL |  |  |  |  |  |
Property, plant and equipment, net |  | $17 |  |  |  | $10 |  |  |  | $7 |  |  |  |  |  |  |
Other current liabilities |  | $2 |  |  |  | $1 |  |  |  | $1 |  |  |  |  |  |  |
Other liabilities | 15 |  |  | 9 |  |  | 6 |  |  |  |  |  |  |
Total operating lease liabilities |  | $17 |  |  |  | $10 |  |  |  | $7 |  |  |  |  |  |  |
Weighted average remaining lease term | 11 years |  |  | 12 years |  |  | 10 years |  |  |  |  |  |  |
Weighted average discount rate | 4 | % |  | 4 | % |  | 4 | % |  |  |  |  |  |
| Three Months Ended |  | Nine Months Ended
| September 30, 2019 |  | September 30, 2019
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Operating lease cost |  | $1 |  |  |  | $1 |  |  |  | $— |  |  |  | $2 |  |  |  | $1 |  |  |  | $— |

Finance Lease - WPL’s finance lease is an agreement for WPL to lease the Sheboygan Falls Energy Facility from AEF’s Non-utility Generation business through 2025, the initial lease term. WPL is responsible for the operation of the EGU and has exclusive rights to its output. This finance lease contains two lease renewal periods, which are not included in the finance lease obligation, as well as an option to purchase the facility at the end of the initial lease term. WPL’s retail and wholesale rates include recovery of the Sheboygan Falls Energy Facility lease payments. WPL’s finance lease details are as follows (dollars in millions):

| September 30, 2019 |  |
Property, plant and equipment, net |  | $34 |  |  |
Other current liabilities |  | $8 |  |  |
Finance lease obligations - Sheboygan Falls Energy Facility | 54 |  |  |
Total finance lease liabilities |  | $62 |  |  |
Remaining lease term | 6 years |  |  |
Discount rate | 11 | % |  |
| Three Months Ended |  | Nine Months Ended
| September 30, 2019 |  | September 30, 2019
Depreciation expense |  | $1 |  |  |  | $4 |
Interest expense | 1 |  |  | 5 |
Total finance lease expense |  | $2 |  |  |  | $9 |

Expected Maturities - As of September 30, 2019, expected maturities of lease liabilities were as follows (in millions):

| Remainder of 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy |  | $— |  |  |  | $2 |  |  |  | $2 |  |  |  | $2 |  |  |  | $2 |  |  |  | $13 |  |  |  | $21 |  |  |  | $4 |  |  |  | $17 |
IPL | — |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 9 |  |  | 13 |  |  | 3 |  |  | 10 |
WPL | — |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 4 |  |  | 8 |  |  | 1 |  |  | 7 |
WPL’s Finance Lease: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sheboygan Falls Energy Facility | 4 |  |  | 15 |  |  | 15 |  |  | 15 |  |  | 15 |  |  | 20 |  |  | 84 |  |  | 22 |  |  | 62 |

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Prior period amounts have not been restated to reflect the adoption of the new lease accounting standard and continue to be reported under the accounting standards in effect for those periods. As of December 31, 2018, future minimum operating (excluding contingent rentals) and capital lease payments were as follows (in millions):

| 2019 |  | 2020 |  | 2021 |  | 2022 |  | 2023 |  | Thereafter |  | Total |  | Less: amount representing interest |  | Present value of minimum capital lease payments
Operating Leases: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Alliant Energy |  | $5 |  |  |  | $5 |  |  |  | $3 |  |  |  | $3 |  |  |  | $2 |  |  |  | $12 |  |  |  | $30 |  |  |  |  |
IPL | 3 |  |  | 2 |  |  | 2 |  |  | 2 |  |  | 2 |  |  | 12 |  |  | 23 |  |  |  |  |
WPL | 2 |  |  | 3 |  |  | 1 |  |  | — |  |  | — |  |  | — |  |  | 6 |  |  |  |  |
WPL’s Capital Lease: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sheboygan Falls Energy Facility |  | $15 |  |  |  | $15 |  |  |  | $15 |  |  |  | $15 |  |  |  | $15 |  |  |  | $19 |  |  |  | $94 |  |  |  | $26 |  |  |  | $68 |

NOTE 8. REVENUES
Disaggregation of revenues from contracts with customers, which correlates to revenues for each reportable segment, was as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $331.6 |  |  |  | $312.9 |  |  |  | $196.0 |  |  |  | $180.1 |  |  |  | $135.6 |  |  |  | $132.8 |
Retail - commercial | 230.9 |  |  | 215.4 |  |  | 158.4 |  |  | 146.0 |  |  | 72.5 |  |  | 69.4 |
Retail - industrial | 263.4 |  |  | 247.8 |  |  | 157.5 |  |  | 141.4 |  |  | 105.9 |  |  | 106.4 |
Wholesale | 49.8 |  |  | 50.0 |  |  | 17.7 |  |  | 18.2 |  |  | 32.1 |  |  | 31.8 |
Bulk power and other | 40.2 |  |  | 35.1 |  |  | 31.3 |  |  | 23.5 |  |  | 8.9 |  |  | 11.6 |
Total Electric Utility | 915.9 |  |  | 861.2 |  |  | 560.9 |  |  | 509.2 |  |  | 355.0 |  |  | 352.0 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 20.4 |  |  | 21.8 |  |  | 11.7 |  |  | 12.6 |  |  | 8.7 |  |  | 9.2 |
Retail - commercial | 10.0 |  |  | 11.0 |  |  | 5.9 |  |  | 6.4 |  |  | 4.1 |  |  | 4.6 |
Retail - industrial | 2.3 |  |  | 3.0 |  |  | 1.9 |  |  | 2.0 |  |  | 0.4 |  |  | 1.0 |
Transportation/other | 8.8 |  |  | 9.0 |  |  | 5.3 |  |  | 5.7 |  |  | 3.5 |  |  | 3.3 |
Total Gas Utility | 41.5 |  |  | 44.8 |  |  | 24.8 |  |  | 26.7 |  |  | 16.7 |  |  | 18.1 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 9.1 |  |  | 8.7 |  |  | 9.1 |  |  | 8.7 |  |  | — |  |  | — |
Other utility | 2.1 |  |  | 3.6 |  |  | 1.7 |  |  | 3.0 |  |  | 0.4 |  |  | 0.6 |
Total Other Utility | 11.2 |  |  | 12.3 |  |  | 10.8 |  |  | 11.7 |  |  | 0.4 |  |  | 0.6 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 21.6 |  |  | 10.3 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 21.6 |  |  | 10.3 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $990.2 |  |  |  | $928.6 |  |  |  | $596.5 |  |  |  | $547.6 |  |  |  | $372.1 |  |  |  | $370.7 |

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| Alliant Energy |  | IPL |  | WPL
Nine Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Electric Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential |  | $839.6 |  |  |  | $820.6 |  |  |  | $469.4 |  |  |  | $461.6 |  |  |  | $370.2 |  |  |  | $359.0 |
Retail - commercial | 583.3 |  |  | 561.7 |  |  | 386.4 |  |  | 371.8 |  |  | 196.9 |  |  | 189.9 |
Retail - industrial | 686.3 |  |  | 675.1 |  |  | 392.0 |  |  | 385.0 |  |  | 294.3 |  |  | 290.1 |
Wholesale | 137.3 |  |  | 146.9 |  |  | 49.2 |  |  | 56.4 |  |  | 88.1 |  |  | 90.5 |
Bulk power and other | 104.0 |  |  | 91.9 |  |  | 76.0 |  |  | 62.2 |  |  | 28.0 |  |  | 29.7 |
Total Electric Utility | 2,350.5 |  |  | 2,296.2 |  |  | 1,373.0 |  |  | 1,337.0 |  |  | 977.5 |  |  | 959.2 |
Gas Utility: |  |  |  |  |  |  |  |  |  |  |
Retail - residential | 187.4 |  |  | 170.1 |  |  | 109.6 |  |  | 100.9 |  |  | 77.8 |  |  | 69.2 |
Retail - commercial | 89.7 |  |  | 87.3 |  |  | 49.5 |  |  | 49.8 |  |  | 40.2 |  |  | 37.5 |
Retail - industrial | 9.7 |  |  | 11.4 |  |  | 6.7 |  |  | 6.1 |  |  | 3.0 |  |  | 5.3 |
Transportation/other | 35.7 |  |  | 30.2 |  |  | 22.0 |  |  | 20.2 |  |  | 13.7 |  |  | 10.0 |
Total Gas Utility | 322.5 |  |  | 299.0 |  |  | 187.8 |  |  | 177.0 |  |  | 134.7 |  |  | 122.0 |
Other Utility: |  |  |  |  |  |  |  |  |  |  |
Steam | 26.7 |  |  | 26.5 |  |  | 26.7 |  |  | 26.5 |  |  | — |  |  | — |
Other utility | 6.5 |  |  | 9.7 |  |  | 5.3 |  |  | 7.7 |  |  | 1.2 |  |  | 2.0 |
Total Other Utility | 33.2 |  |  | 36.2 |  |  | 32.0 |  |  | 34.2 |  |  | 1.2 |  |  | 2.0 |
Non-Utility and Other: |  |  |  |  |  |  |  |  |  |  |
Transportation and other | 61.4 |  |  | 29.6 |  |  | — |  |  | — |  |  | — |  |  | — |
Total Non-Utility and Other | 61.4 |  |  | 29.6 |  |  | — |  |  | — |  |  | — |  |  | — |
Total revenues |  | $2,767.6 |  |  |  | $2,661.0 |  |  |  | $1,592.8 |  |  |  | $1,548.2 |  |  |  | $1,113.4 |  |  |  | $1,083.2 |

NOTE 9. INCOME TAXES
Income Tax Rates - The overall income tax rates shown in the following table were computed by dividing income taxes by income before income taxes.

| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Statutory federal income tax rate | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | %
State income taxes, net of federal benefits | 7.0 |  |  | 6.9 |  |  | 8.1 |  |  | 7.7 |  |  | 6.2 |  |  | 6.2 |
Production tax credits | (9.3 | ) |  | (5.4 | ) |  | (14.7 | ) |  | (5.5 | ) |  | (4.4 | ) |  | (6.4 | )
Effect of rate-making on property-related differences | (5.6 | ) |  | (6.3 | ) |  | (9.0 | ) |  | (11.5 | ) |  | (2.8 | ) |  | (2.1 | )
Amortization of excess deferred taxes | (1.1 | ) |  | (0.1 | ) |  | (0.3 | ) |  | — |  |  | (1.7 | ) |  | (0.1 | )
Adjustment for prior period taxes | (1.8 | ) |  | (5.7 | ) |  | 1.3 |  |  | (10.2 | ) |  | 0.4 |  |  | — |
IPL’s tax benefit riders | (0.8 | ) |  | (2.3 | ) |  | (1.5 | ) |  | (4.8 | ) |  | — |  |  | — |
Federal Tax Reform adjustments | — |  |  | (2.5 | ) |  | — |  |  | (0.9 | ) |  | — |  |  | (6.4 | )
Other items, net | (0.2 | ) |  | (0.3 | ) |  | (0.3 | ) |  | (0.6 | ) |  | (0.2 | ) |  | (0.4 | )
Overall income tax rate | 9.2 | % |  | 5.3 | % |  | 4.6 | % |  | (4.8 | %) |  | 18.5 | % |  | 11.8 | %

| Alliant Energy |  | IPL |  | WPL
Nine Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Statutory federal income tax rate | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | % |  | 21.0 | %
State income taxes, net of federal benefits | 7.1 |  |  | 6.9 |  |  | 8.1 |  |  | 7.7 |  |  | 6.2 |  |  | 6.2 |
Production tax credits | (9.1 | ) |  | (5.4 | ) |  | (14.3 | ) |  | (5.4 | ) |  | (4.5 | ) |  | (6.6 | )
Effect of rate-making on property-related differences | (5.7 | ) |  | (6.7 | ) |  | (9.3 | ) |  | (12.0 | ) |  | (2.6 | ) |  | (2.3 | )
Amortization of excess deferred taxes | (1.1 | ) |  | (0.3 | ) |  | (0.3 | ) |  | — |  |  | (1.7 | ) |  | (0.1 | )
Adjustment for prior period taxes | (0.7 | ) |  | (2.6 | ) |  | 0.6 |  |  | (5.4 | ) |  | (0.3 | ) |  | — |
IPL’s tax benefit riders | (0.7 | ) |  | (2.2 | ) |  | (1.5 | ) |  | (4.6 | ) |  | — |  |  | — |
Federal Tax Reform adjustments | — |  |  | (1.2 | ) |  | — |  |  | (0.5 | ) |  | — |  |  | (2.8 | )
Other items, net | (1.0 | ) |  | (0.7 | ) |  | (0.1 | ) |  | (1.0 | ) |  | (0.4 | ) |  | (1.2 | )
Overall income tax rate | 9.8 | % |  | 8.8 | % |  | 4.2 | % |  | (0.2 | %) |  | 17.7 | % |  | 14.2 | %

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Deferred Tax Assets and Liabilities -
Carryforwards - At September 30, 2019, carryforwards and expiration dates were estimated as follows (in millions):

| Range of Expiration Dates |  | Alliant Energy |  | IPL |  | WPL
Federal net operating losses | 2031-2037 |  |  | $611 |  |  |  | $522 |  |  |  | $41 |
State net operating losses | 2019-2039 |  | 677 |  |  | 12 |  |  | 2 |
Federal tax credits | 2022-2039 |  | 337 |  |  | 162 |  |  | 156 |

NOTE 10. BENEFIT PLANS
NOTE 10(a) Pension and OPEB Plans -
Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three and nine months ended September 30 are included below (in millions). For IPL and WPL, amounts represent their current and former employees covered under plans they sponsor, as well as amounts directly assigned to them related to their current and former employees who are participants in the Alliant Energy and Corporate Services sponsored plans.

| Defined Benefit Pension Plans |  | OPEB Plans
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
Alliant Energy | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Service cost |  | $2.5 |  |  |  | $3.1 |  |  |  | $7.3 |  |  |  | $9.1 |  |  |  | $0.8 |  |  |  | $1.0 |  |  |  | $2.5 |  |  |  | $3.1 |
Interest cost | 12.5 |  |  | 11.7 |  |  | 37.4 |  |  | 35.1 |  |  | 2.2 |  |  | 2.0 |  |  | 6.4 |  |  | 5.8 |
Expected return on plan assets | (15.1 | ) |  | (17.4 | ) |  | (45.1 | ) |  | (52.3 | ) |  | (1.2 | ) |  | (1.5 | ) |  | (3.7 | ) |  | (4.5 | )
Amortization of prior service credit | (0.2 | ) |  | (0.2 | ) |  | (0.5 | ) |  | (0.5 | ) |  | (0.1 | ) |  | — |  |  | (0.2 | ) |  | (0.1 | )
Amortization of actuarial loss | 9.1 |  |  | 8.8 |  |  | 27.3 |  |  | 26.4 |  |  | 0.8 |  |  | 0.8 |  |  | 2.4 |  |  | 2.5 |
|  | $8.8 |  |  |  | $6.0 |  |  |  | $26.4 |  |  |  | $17.8 |  |  |  | $2.5 |  |  |  | $2.3 |  |  |  | $7.4 |  |  |  | $6.8 |

| Defined Benefit Pension Plans |  | OPEB Plans
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
IPL | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Service cost |  | $1.6 |  |  |  | $1.8 |  |  |  | $4.6 |  |  |  | $5.5 |  |  |  | $0.3 |  |  |  | $0.4 |  |  |  | $1.0 |  |  |  | $1.3 |
Interest cost | 5.6 |  |  | 5.3 |  |  | 17.0 |  |  | 16.0 |  |  | 0.8 |  |  | 0.7 |  |  | 2.5 |  |  | 2.3 |
Expected return on plan assets | (7.0 | ) |  | (8.1 | ) |  | (21.1 | ) |  | (24.4 | ) |  | (0.9 | ) |  | (1.1 | ) |  | (2.7 | ) |  | (3.3 | )
Amortization of prior service credit | (0.1 | ) |  | — |  |  | (0.2 | ) |  | (0.1 | ) |  | — |  |  | — |  |  | — |  |  | — |
Amortization of actuarial loss | 3.9 |  |  | 3.7 |  |  | 11.8 |  |  | 11.2 |  |  | 0.4 |  |  | 0.4 |  |  | 1.1 |  |  | 1.0 |
|  | $4.0 |  |  |  | $2.7 |  |  |  | $12.1 |  |  |  | $8.2 |  |  |  | $0.6 |  |  |  | $0.4 |  |  |  | $1.9 |  |  |  | $1.3 |

| Defined Benefit Pension Plans |  | OPEB Plans
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
WPL | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Service cost |  | $0.9 |  |  |  | $1.1 |  |  |  | $2.6 |  |  |  | $3.3 |  |  |  | $0.3 |  |  |  | $0.4 |  |  |  | $0.9 |  |  |  | $1.2 |
Interest cost | 5.3 |  |  | 5.0 |  |  | 16.1 |  |  | 15.1 |  |  | 0.9 |  |  | 0.8 |  |  | 2.6 |  |  | 2.3 |
Expected return on plan assets | (6.5 | ) |  | (7.6 | ) |  | (19.6 | ) |  | (22.8 | ) |  | (0.2 | ) |  | (0.2 | ) |  | (0.5 | ) |  | (0.5 | )
Amortization of prior service credit | — |  |  | — |  |  | (0.1 | ) |  | (0.1 | ) |  | — |  |  | — |  |  | (0.1 | ) |  | (0.1 | )
Amortization of actuarial loss | 4.4 |  |  | 4.3 |  |  | 13.2 |  |  | 12.9 |  |  | 0.4 |  |  | 0.5 |  |  | 1.2 |  |  | 1.5 |
|  | $4.1 |  |  |  | $2.8 |  |  |  | $12.2 |  |  |  | $8.4 |  |  |  | $1.4 |  |  |  | $1.5 |  |  |  | $4.1 |  |  |  | $4.4 |

NOTE 10(b) Equity-based Compensation Plans - A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three and nine months ended September 30 was as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Compensation expense |  | $7.5 |  |  |  | $4.2 |  |  |  | $15.6 |  |  |  | $12.6 |  |  |  | $4.2 |  |  |  | $2.4 |  |  |  | $8.7 |  |  |  | $7.0 |  |  |  | $3.0 |  |  |  | $1.7 |  |  |  | $6.2 |  |  |  | $5.1 |
Income tax benefits | 2.1 |  |  | 1.2 |  |  | 4.4 |  |  | 3.6 |  |  | 1.2 |  |  | 0.7 |  |  | 2.5 |  |  | 2.1 |  |  | 0.8 |  |  | 0.5 |  |  | 1.7 |  |  | 1.4 |

As of September 30, 2019, Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $7.2 million, $4.0 million and $2.9 million, respectively, which is expected to be recognized over a weighted average period of between 1 and 2 years.

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For the nine months ended September 30, 2019, performance shares, performance restricted stock units and restricted stock units were granted to key employees and will be paid out in shares, and are therefore accounted for as equity awards. The 2019 performance shares contain a market condition based on total shareowner return relative to an investor-owned utility peer group. The fair value of each performance share is based on the fair value of the underlying common stock on the grant date and the probability of satisfying the market condition contained in the agreement during a 3-year performance period. For the nine months ended September 30, 2019, 91,816 performance shares were granted with a weighted average grant date fair value of $47.23. The 2019 performance restricted stock units will vest based on the achievement of certain targets (specified growth of consolidated net income from continuing operations) during a 3-year performance period. The actual number of performance shares and performance restricted units that will be paid out upon vesting is dependent upon actual performance and may range from zero to 200% of the target number of shares or units, as applicable. The 2019 restricted stock units will vest based on the expiration of a 3-year time-vesting period. For the nine months ended September 30, 2019, 91,816 performance restricted stock units were granted with a weighted average grant date fair value of $46.10, and 105,348 restricted stock units were granted with a weighted average grant date fair value of $45.98, which is based on the closing market price of one share of Alliant Energy’s common stock on the grant date of the award. As of September 30, 2019, 122,720 shares were included in the calculation of diluted EPS related to the nonvested equity awards.
NOTE 11. ASSET RETIREMENT OBLIGATIONS
A reconciliation of the changes in asset retirement obligations associated with long-lived assets for the nine months ended September 30, 2019 is as follows (in millions):

| Alliant Energy |  | IPL
Balance, January 1 |  | $177.5 |  |  |  | $118.3 |
Revisions in estimated cash flows | (5.8 | ) |  | (7.0 | )
Liabilities settled | (5.9 | ) |  | (5.6 | )
Liabilities incurred (a) | 26.2 |  |  | 26.2 |
Accretion expense | 5.3 |  |  | 3.5 |
Balance, September 30 |  | $197.3 |  |  |  | $135.4 |

(a) | During the nine months ended September 30, 2019, Alliant Energy and IPL recognized additional asset retirement obligations related to IPL’s newly constructed Upland Prairie and English Farms wind sites. The increases in asset retirement obligations resulted in corresponding increases in property, plant and equipment, net on the respective balance sheets.

NOTE 12. DERIVATIVE INSTRUMENTS
Commodity Derivatives -
Notional Amounts - As of September 30, 2019, gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts and FTRs that were accounted for as commodity derivative instruments were as follows (units in thousands):

| FTRs |  | Natural Gas |  | Coal |  | Diesel Fuel
| MWhs |  | Years |  | Dths |  | Years |  | Tons |  | Years |  | Gallons |  | Years
Alliant Energy | 18,141 |  |  | 2019-2020 |  | 184,007 |  |  | 2019-2026 |  | 7,620 |  |  | 2019-2021 |  | 5,796 |  |  | 2019-2021
IPL | 8,630 |  |  | 2019-2020 |  | 101,579 |  |  | 2019-2026 |  | 3,311 |  |  | 2019-2021 |  | — |  |  | —
WPL | 9,511 |  |  | 2019-2020 |  | 82,428 |  |  | 2019-2026 |  | 4,309 |  |  | 2019-2021 |  | 5,796 |  |  | 2019-2021

Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
| September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018
Current derivative assets |  | $18.6 |  |  |  | $24.6 |  |  |  | $12.8 |  |  |  | $16.1 |  |  |  | $5.8 |  |  |  | $8.5 |
Non-current derivative assets | 11.7 |  |  | 3.7 |  |  | 10.5 |  |  | 1.6 |  |  | 1.2 |  |  | 2.1 |
Current derivative liabilities | 13.4 |  |  | 5.6 |  |  | 5.6 |  |  | 3.1 |  |  | 7.8 |  |  | 2.5 |
Non-current derivative liabilities | 18.4 |  |  | 17.7 |  |  | 7.8 |  |  | 8.1 |  |  | 10.6 |  |  | 9.6 |

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Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At September 30, 2019 and December 31, 2018, the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered.
Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at September 30, 2019 and December 31, 2018. Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement.
NOTE 13. FAIR VALUE MEASUREMENTS
Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions):

Alliant Energy | September 30, 2019 |  | December 31, 2018
|  |  | Fair Value |  |  |  | Fair Value
| Carrying |  | Level |  | Level |  | Level |  |  |  | Carrying |  | Level |  | Level |  | Level |  |
| Amount |  | 1 |  | 2 |  | 3 |  | Total |  | Amount |  | 1 |  | 2 |  | 3 |  | Total
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Money market fund investments |  | $174.4 |  |  |  | $174.4 |  |  |  | $— |  |  |  | $— |  |  |  | $174.4 |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Derivatives | 30.3 |  |  | — |  |  | 8.1 |  |  | 22.2 |  |  | 30.3 |  |  | 28.3 |  |  | — |  |  | 8.9 |  |  | 19.4 |  |  | 28.3 |
Deferred proceeds | 237.0 |  |  | — |  |  | — |  |  | 237.0 |  |  | 237.0 |  |  | 119.4 |  |  | — |  |  | — |  |  | 119.4 |  |  | 119.4 |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives | 31.8 |  |  | — |  |  | 31.3 |  |  | 0.5 |  |  | 31.8 |  |  | 23.3 |  |  | — |  |  | 16.1 |  |  | 7.2 |  |  | 23.3 |
Long-term debt (incl. current maturities) | 6,191.9 |  |  | — |  |  | 7,016.4 |  |  | 2.0 |  |  | 7,018.4 |  |  | 5,502.8 |  |  | — |  |  | 5,858.4 |  |  | 2.4 |  |  | 5,860.8 |

IPL | September 30, 2019 |  | December 31, 2018
|  |  | Fair Value |  |  |  | Fair Value
| Carrying |  | Level |  | Level |  | Level |  |  |  | Carrying |  | Level |  | Level |  | Level |  |
| Amount |  | 1 |  | 2 |  | 3 |  | Total |  | Amount |  | 1 |  | 2 |  | 3 |  | Total
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Money market fund investments |  | $173.7 |  |  |  | $173.7 |  |  |  | $— |  |  |  | $— |  |  |  | $173.7 |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $— |
Derivatives | 23.3 |  |  | — |  |  | 4.8 |  |  | 18.5 |  |  | 23.3 |  |  | 17.7 |  |  | — |  |  | 4.0 |  |  | 13.7 |  |  | 17.7 |
Deferred proceeds | 237.0 |  |  | — |  |  | — |  |  | 237.0 |  |  | 237.0 |  |  | 119.4 |  |  | — |  |  | — |  |  | 119.4 |  |  | 119.4 |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives | 13.4 |  |  | — |  |  | 12.9 |  |  | 0.5 |  |  | 13.4 |  |  | 11.2 |  |  | — |  |  | 6.5 |  |  | 4.7 |  |  | 11.2 |
Long-term debt (incl. current maturities) | 3,146.8 |  |  | — |  |  | 3,537.0 |  |  | — |  |  | 3,537.0 |  |  | 2,552.3 |  |  | — |  |  | 2,691.2 |  |  | — |  |  | 2,691.2 |

WPL | September 30, 2019 |  | December 31, 2018
|  |  | Fair Value |  |  |  | Fair Value
| Carrying |  | Level |  | Level |  | Level |  |  |  | Carrying |  | Level |  | Level |  | Level |  |
| Amount |  | 1 |  | 2 |  | 3 |  | Total |  | Amount |  | 1 |  | 2 |  | 3 |  | Total
Assets: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives |  | $7.0 |  |  |  | $— |  |  |  | $3.3 |  |  |  | $3.7 |  |  |  | $7.0 |  |  |  | $10.6 |  |  |  | $— |  |  |  | $4.9 |  |  |  | $5.7 |  |  |  | $10.6 |
Liabilities: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives | 18.4 |  |  | — |  |  | 18.4 |  |  | — |  |  | 18.4 |  |  | 12.1 |  |  | — |  |  | 9.6 |  |  | 2.5 |  |  | 12.1 |
Long-term debt (incl. current maturities) | 1,932.3 |  |  | — |  |  | 2,314.1 |  |  | — |  |  | 2,314.1 |  |  | 1,834.9 |  |  | — |  |  | 2,043.7 |  |  | — |  |  | 2,043.7 |

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Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions):

Alliant Energy | Commodity Contract Derivative |  |
| Assets and (Liabilities), net |  | Deferred Proceeds
Three Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018
Beginning balance, July 1 |  | $13.2 |  |  |  | ($10.7 | ) |  |  | $214.6 |  |  |  | $208.3 |
Total net gains included in changes in net assets (realized/unrealized) | 12.7 |  |  | 25.7 |  |  | — |  |  | — |
Transfers out of Level 3 | (1.2 | ) |  | 15.6 |  |  | — |  |  | — |
Sales | — |  |  | (0.2 | ) |  | — |  |  | — |
Settlements (a) | (3.0 | ) |  | (6.2 | ) |  | 22.4 |  |  | 35.4 |
Ending balance, September 30 |  | $21.7 |  |  |  | $24.2 |  |  |  | $237.0 |  |  |  | $243.7 |
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at September 30 |  | $12.7 |  |  |  | $26.1 |  |  |  | $— |  |  |  | $— |

Alliant Energy | Commodity Contract Derivative |  |
| Assets and (Liabilities), net |  | Deferred Proceeds
Nine Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018
Beginning balance, January 1 |  | $12.2 |  |  |  | ($12.2 | ) |  |  | $119.4 |  |  |  | $222.1 |
Total net gains included in changes in net assets (realized/unrealized) | 6.9 |  |  | 15.7 |  |  | — |  |  | — |
Transfers out of Level 3 | 2.8 |  |  | 15.6 |  |  | — |  |  | — |
Purchases | 13.8 |  |  | 26.7 |  |  | — |  |  | — |
Sales | (0.2 | ) |  | (0.2 | ) |  | — |  |  | — |
Settlements (a) | (13.8 | ) |  | (21.4 | ) |  | 117.6 |  |  | 21.6 |
Ending balance, September 30 |  | $21.7 |  |  |  | $24.2 |  |  |  | $237.0 |  |  |  | $243.7 |
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at September 30 |  | $10.1 |  |  |  | $16.5 |  |  |  | $— |  |  |  | $— |

IPL | Commodity Contract Derivative |  |
| Assets and (Liabilities), net |  | Deferred Proceeds
Three Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018
Beginning balance, July 1 |  | $9.3 |  |  |  | ($4.1 | ) |  |  | $214.6 |  |  |  | $208.3 |
Total net gains included in changes in net assets (realized/unrealized) | 11.5 |  |  | 16.8 |  |  | — |  |  | — |
Transfers out of Level 3 | (0.6 | ) |  | 10.5 |  |  | — |  |  | — |
Sales | — |  |  | (0.1 | ) |  | — |  |  | — |
Settlements (a) | (2.2 | ) |  | (4.9 | ) |  | 22.4 |  |  | 35.4 |
Ending balance, September 30 |  | $18.0 |  |  |  | $18.2 |  |  |  | $237.0 |  |  |  | $243.7 |
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at September 30 |  | $11.5 |  |  |  | $16.8 |  |  |  | $— |  |  |  | $— |

IPL | Commodity Contract Derivative |  |
| Assets and (Liabilities), net |  | Deferred Proceeds
Nine Months Ended September 30 | 2019 |  | 2018 |  | 2019 |  | 2018
Beginning balance, January 1 |  | $9.0 |  |  |  | ($1.4 | ) |  |  | $119.4 |  |  |  | $222.1 |
Total net gains included in changes in net assets (realized/unrealized) | 8.6 |  |  | 7.6 |  |  | — |  |  | — |
Transfers out of Level 3 | 2.0 |  |  | 10.5 |  |  | — |  |  | — |
Purchases | 9.5 |  |  | 19.3 |  |  | — |  |  | — |
Sales | (0.1 | ) |  | (0.1 | ) |  | — |  |  | — |
Settlements (a) | (11.0 | ) |  | (17.7 | ) |  | 117.6 |  |  | 21.6 |
Ending balance, September 30 |  | $18.0 |  |  |  | $18.2 |  |  |  | $237.0 |  |  |  | $243.7 |
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at September 30 |  | $10.5 |  |  |  | $7.9 |  |  |  | $— |  |  |  | $— |

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WPL | Commodity Contract Derivative
| Assets and (Liabilities), net
Three Months Ended September 30 | 2019 |  | 2018
Beginning balance, July 1 |  | $3.9 |  |  |  | ($6.6 | )
Total net gains included in changes in net assets (realized/unrealized) | 1.2 |  |  | 8.9 |
Transfers out of Level 3 | (0.6 | ) |  | 5.1 |
Sales | — |  |  | (0.1 | )
Settlements | (0.8 | ) |  | (1.3 | )
Ending balance, September 30 |  | $3.7 |  |  |  | $6.0 |
The amount of total net gains for the period included in changes in net assets attributable to the change in unrealized gains relating to assets and liabilities held at September 30 |  | $1.2 |  |  |  | $9.3 |

WPL | Commodity Contract Derivative
| Assets and (Liabilities), net
Nine Months Ended September 30 | 2019 |  | 2018
Beginning balance, January 1 |  | $3.2 |  |  |  | ($10.8 | )
Total net gains (losses) included in changes in net assets (realized/unrealized) | (1.7 | ) |  | 8.1 |
Transfers out of Level 3 | 0.8 |  |  | 5.1 |
Purchases | 4.3 |  |  | 7.4 |
Sales | (0.1 | ) |  | (0.1 | )
Settlements | (2.8 | ) |  | (3.7 | )
Ending balance, September 30 |  | $3.7 |  |  |  | $6.0 |
The amount of total net gains (losses) for the period included in changes in net assets attributable to the change in unrealized gains (losses) relating to assets and liabilities held at September 30 |  | ($0.4 | ) |  |  | $8.6 |

(a) | Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold.

Commodity Contracts - The fair value of FTR and natural gas commodity contracts categorized as Level 3 was recognized as net derivative assets as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
| Excluding FTRs |  | FTRs |  | Excluding FTRs |  | FTRs |  | Excluding FTRs |  | FTRs
September 30, 2019 |  | $13.1 |  |  |  | $8.6 |  |  |  | $12.5 |  |  |  | $5.5 |  |  |  | $0.6 |  |  |  | $3.1 |
December 31, 2018 | 3.2 |  |  | 9.0 |  |  | 1.8 |  |  | 7.2 |  |  | 1.4 |  |  | 1.8 |

NOTE 14. COMMITMENTS AND CONTINGENCIES
NOTE 14(a) Capital Purchase Commitments - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s and WPL’s projects include the expansion of wind generation, and WPL’s projects also include the West Riverside Energy Center. At September 30, 2019, Alliant Energy’s, IPL’s and WPL’s minimum future commitments for these projects were $124 million, $79 million and $45 million, respectively.
NOTE 14(b) Other Purchase Commitments - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. In addition, there are various purchase commitments associated with other goods and services. At September 30, 2019, the related minimum future commitments were as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
Purchased power (a) |  | $145 |  |  |  | $144 |  |  |  | $1 |
Natural gas | 892 |  |  | 460 |  |  | 432 |
Coal (b) | 117 |  |  | 76 |  |  | 41 |
Other (c) | 76 |  |  | 43 |  |  | 24 |
|  | $1,230 |  |  |  | $723 |  |  |  | $498 |

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(a) | Includes payments required by PPAs for capacity rights and minimum quantities of MWhs required to be purchased. As a result of an amendment to shorten the term of the DAEC PPA, Alliant Energy’s and IPL’s amounts include minimum future commitments related to IPL’s purchase of capacity and the resulting energy from DAEC through September 2020, and do not include the September 2020 buyout payment of $110 million.

(b) | Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of September 30, 2019 regarding expected future usage, which is subject to change.

(c) | Includes individual commitments incurred during the normal course of business that exceeded $1 million at September 30, 2019.

NOTE 14(c) Guarantees and Indemnifications -
Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under general partnership agreements in the oil and gas industry, including with respect to the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The guarantees do not include a maximum limit. As of September 30, 2019, the present value of the abandonment obligations is estimated at $38 million. Alliant Energy is not aware of any material liabilities related to these guarantees of which it is probable that Alliant Energy Resources, LLC will be obligated to pay and therefore has not recognized any material liabilities related to these guarantees as of September 30, 2019 and December 31, 2018.
Non-utility Wind Farm in Oklahoma - In July 2017, a wholly-owned subsidiary of AEF acquired a cash equity ownership interest in a non-utility wind farm located in Oklahoma. The wind farm provides electricity to a third-party under a long-term PPA. Alliant Energy provided a parent guarantee of its subsidiary’s indemnification obligations under the related operating agreement and PPA. Alliant Energy’s obligations under the operating agreement were $82 million as of September 30, 2019 and will reduce annually until expiring in July 2047. Alliant Energy’s obligations under the PPA are subject to a maximum limit of $17 million and expire in December 2031, subject to potential extension. Alliant Energy is not aware of any material liabilities related to this guarantee that it is probable that it will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of September 30, 2019 and December 31, 2018.
IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of September 30, 2019 and December 31, 2018. The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020.
NOTE 14(d) Environmental Matters -
Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. At September 30, 2019, estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, which are not discounted, were as follows (in millions). At September 30, 2019, such amounts for WPL were not material.

| Alliant Energy |  | IPL
Range of estimated future costs |  | $14 |  | - | $31 |  |  | $12 |  | - | $25
Current and non-current environmental liabilities | 19 |  | 16

IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential Clean Air Act issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include fuel switching or retiring Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to compliance with the terms of the Consent Decree from IPL’s electric customers.

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Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including the Clean Air Act.
Clean Air Act Section 111(d) - In July 2019, the EPA published the final Affordable Clean Energy rule, which repeals the Clean Power Plan effective September 6, 2019. The final rule establishes emission guidelines for states to develop plans by July 2022 to reduce carbon dioxide emissions from existing coal-fired EGUs, and is subject to legal challenges. Alliant Energy, IPL and WPL are currently unable to predict with certainty the final outcome or impact of these matters.
NOTE 14(e) Collective Bargaining Agreements - At September 30, 2019, employees covered by collective bargaining agreements represented 54%, 60% and 82% of total employees of Alliant Energy, IPL and WPL, respectively. On May 31, 2019, WPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 965 expired, representing 27% and 82% of total employees of Alliant Energy and WPL, respectively. In November 2019, the parties reached a new agreement, which expires May 31, 2022.
NOTE 15. SEGMENTS OF BUSINESS
Alliant Energy - Certain financial information relating to Alliant Energy’s business segments is as follows. Intersegment revenues were not material to Alliant Energy’s operations.

|  |  |  |  |  |  |  |  | ATC Holdings, |  | Alliant
| Utility |  | Non-Utility, |  | Energy
| Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
| (in millions)
Three Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $915.9 |  |  |  | $41.5 |  |  |  | $11.2 |  |  |  | $968.6 |  |  |  | $21.6 |  |  |  | $990.2 |
Operating income (loss) | 283.7 |  |  | (4.7 | ) |  | 2.8 |  |  | 281.8 |  |  | 8.4 |  |  | 290.2 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 216.6 |  |  | 9.4 |  |  | 226.0 |
Three Months Ended September 30, 2018 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $861.2 |  |  |  | $44.8 |  |  |  | $12.3 |  |  |  | $918.3 |  |  |  | $10.3 |  |  |  | $928.6 |
Operating income (loss) | 248.7 |  |  | (2.0 | ) |  | 0.6 |  |  | 247.3 |  |  | 8.8 |  |  | 256.1 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 202.8 |  |  | 2.7 |  |  | 205.5 |

|  |  |  |  |  |  |  |  | ATC Holdings, |  | Alliant
| Utility |  | Non-Utility, |  | Energy
| Electric |  | Gas |  | Other |  | Total |  | Parent and Other |  | Consolidated
| (in millions)
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,350.5 |  |  |  | $322.5 |  |  |  | $33.2 |  |  |  | $2,706.2 |  |  |  | $61.4 |  |  |  | $2,767.6 |
Operating income | 543.0 |  |  | 47.7 |  |  | 4.2 |  |  | 594.9 |  |  | 21.9 |  |  | 616.8 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 422.6 |  |  | 23.1 |  |  | 445.7 |
Nine Months Ended September 30, 2018 |  |  |  |  |  |  |  |  |  |  |
Revenues |  | $2,296.2 |  |  |  | $299.0 |  |  |  | $36.2 |  |  |  | $2,631.4 |  |  |  | $29.6 |  |  |  | $2,661.0 |
Operating income | 510.2 |  |  | 34.9 |  |  | 2.9 |  |  | 548.0 |  |  | 25.0 |  |  | 573.0 |
Net income attributable to Alliant Energy common shareowners |  |  |  |  |  |  | 395.0 |  |  | 31.8 |  |  | 426.8 |

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IPL - Certain financial information relating to IPL’s business segments is as follows. Intersegment revenues were not material to IPL’s operations.

| Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $560.9 |  |  |  | $24.8 |  |  |  | $10.8 |  |  |  | $596.5 |
Operating income (loss) | 175.1 |  |  | (4.2 | ) |  | 2.6 |  |  | 173.5 |
Earnings available for common stock |  |  |  |  |  |  | 141.1 |
Three Months Ended September 30, 2018 |  |  |  |  |  |  |
Revenues |  | $509.2 |  |  |  | $26.7 |  |  |  | $11.7 |  |  |  | $547.6 |
Operating income (loss) | 144.7 |  |  | (3.1 | ) |  | 1.5 |  |  | 143.1 |
Earnings available for common stock |  |  |  |  |  |  | 126.5 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $1,373.0 |  |  |  | $187.8 |  |  |  | $32.0 |  |  |  | $1,592.8 |
Operating income | 290.8 |  |  | 26.3 |  |  | 4.4 |  |  | 321.5 |
Earnings available for common stock |  |  |  |  |  |  | 239.4 |
Nine Months Ended September 30, 2018 |  |  |  |  |  |  |
Revenues |  | $1,337.0 |  |  |  | $177.0 |  |  |  | $34.2 |  |  |  | $1,548.2 |
Operating income | 275.7 |  |  | 16.3 |  |  | 4.4 |  |  | 296.4 |
Earnings available for common stock |  |  |  |  |  |  | 224.9 |

WPL - Certain financial information relating to WPL’s business segments is as follows. Intersegment revenues were not material to WPL’s operations.

| Electric |  | Gas |  | Other |  | Total
| (in millions)
Three Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $355.0 |  |  |  | $16.7 |  |  |  | $0.4 |  |  |  | $372.1 |
Operating income (loss) | 108.6 |  |  | (0.5 | ) |  | 0.2 |  |  | 108.3 |
Earnings available for common stock |  |  |  |  |  |  | 75.5 |
Three Months Ended September 30, 2018 |  |  |  |  |  |  |
Revenues |  | $352.0 |  |  |  | $18.1 |  |  |  | $0.6 |  |  |  | $370.7 |
Operating income (loss) | 104.0 |  |  | 1.1 |  |  | (0.9 | ) |  | 104.2 |
Earnings available for common stock |  |  |  |  |  |  | 76.3 |
Nine Months Ended September 30, 2019 |  |  |  |  |  |  |
Revenues |  | $977.5 |  |  |  | $134.7 |  |  |  | $1.2 |  |  |  | $1,113.4 |
Operating income (loss) | 252.2 |  |  | 21.4 |  |  | (0.2 | ) |  | 273.4 |
Earnings available for common stock |  |  |  |  |  |  | 183.2 |
Nine Months Ended September 30, 2018 |  |  |  |  |  |  |
Revenues |  | $959.2 |  |  |  | $122.0 |  |  |  | $2.0 |  |  |  | $1,083.2 |
Operating income (loss) | 234.5 |  |  | 18.6 |  |  | (1.5 | ) |  | 251.6 |
Earnings available for common stock |  |  |  |  |  |  | 170.1 |

NOTE 16. RELATED PARTIES
Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three and nine months ended September 30 were as follows (in millions):

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| IPL |  | WPL
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Corporate Services billings |  | $47 |  |  |  | $43 |  |  |  | $137 |  |  |  | $128 |  |  |  | $36 |  |  |  | $33 |  |  |  | $104 |  |  |  | $100 |
Sales credited | 23 |  |  | 11 |  |  | 50 |  |  | 34 |  |  | 2 |  |  | 7 |  |  | 6 |  |  | 16 |
Purchases billed | 93 |  |  | 95 |  |  | 251 |  |  | 268 |  |  | 32 |  |  | 19 |  |  | 91 |  |  | 56 |

Net intercompany payables to Corporate Services were as follows (in millions):

| IPL |  | WPL
| September 30, 2019 |  | December 31, 2018 |  | September 30, 2019 |  | December 31, 2018
Net payables to Corporate Services | $108 |  | $95 |  | $75 |  | $71

ATC - Pursuant to various agreements, WPL receives a range of transmission services from ATC. WPL provides operation, maintenance, and construction services to ATC. WPL and ATC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three and nine months ended September 30 were as follows (in millions):

| Three Months |  | Nine Months
| 2019 |  | 2018 |  | 2019 |  | 2018
ATC billings to WPL |  | $28 |  |  |  | $26 |  |  |  | $82 |  |  |  | $79 |
WPL billings to ATC | 3 |  |  | 3 |  |  | 10 |  |  | 8 |

WPL owed ATC net amounts of $9 million as of September 30, 2019 and $8 million as of December 31, 2018.
WPL’s Sheboygan Falls Energy Facility Lease - Refer to Note 7 for discussion of WPL’s Sheboygan Falls Energy Facility lease.
ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS
This MDA includes information relating to Alliant Energy, and IPL and WPL (collectively, the Utilities), as well as ATC Holdings, AEF and Corporate Services. Where appropriate, information relating to a specific entity has been segregated and labeled as such. The following discussion and analysis should be read in conjunction with the Financial Statements and the Notes included in this report, as well as the financial statements, notes and MDA included in the 2018 Form 10-K. Unless otherwise noted, all “per share” references in MDA refer to earnings per diluted share.
2019 HIGHLIGHTS
Key highlights since the filing of the 2018 Form 10-K include the following:
Rate Matters:

• | In March 2019, IPL filed requests with the IUB to increase annual base rates for its Iowa retail electric and gas customers, which were based on a forward-looking test period that includes 2020. IPL concurrently filed for interim retail electric rates based on a 2018 historical Test Year, which were implemented effective April 1, 2019. In October 2019, IPL reached settlement agreements with intervenor groups for annual retail electric and gas base rate increases. The electric base rate agreement includes a return on common equity of 9.5% for all non-advanced rate making principle generating assets and 5% for production tax credit carryforwards for the most recent 1,000 MW of new wind generation development, recovery of the most recent 1,000 MW of new wind generation development through a new renewable energy rider, and a 51% common equity component of regulatory capital structure. The gas base rate agreement includes a return on common equity of 9.6% and a 51% common equity component of regulatory capital structure. Refer to Note 2 for details.

• | In March 2019, the IUB approved IPL’s energy efficiency plan for 2019 through 2023, which provides direct financial savings to customers and provides cost-effective options to help electric and gas customers reduce their energy usage. The energy efficiency costs, which are lower than previous energy efficiency plans, are reflected on electric and gas customer bills beginning June 2019 and November 2019, respectively.

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Customer Investments:

• | In March 2019, IPL placed approximately 470 megawatts of new wind generation in service at the Upland Prairie and English Farms wind sites. IPL’s retail electric customers began to see the rate impacts of this renewable generation with the interim electric rates effective April 1, 2019.

• | In January and March 2019, AEF, a subsidiary of Alliant Energy, purchased two freight management companies. These non-utility acquisitions enhance Alliant Energy’s Transportation value to customers by adding customized supply chain solution capabilities to their portfolio of service offerings. Refer to Note 4 for details.

• | The installation of a selective catalytic reduction system at IPL’s Ottumwa Unit 1 was completed in the first quarter of 2019, which supports compliance obligations under the Cross-State Air Pollution Rule and IPL’s Consent Decree.

• | In September 2019, WPL filed a Certificate of Authority application with the PSCW for approval to expand its gas distribution systems in Western Wisconsin in 2020. Estimated capital expenditures for this project for 2020 are included in the “Gas distribution systems” line in the construction and acquisition expenditures table in “Liquidity and Capital Resources.”

• | Alliant Energy’s cleaner energy strategy includes the planned development and acquisition of up to 1,000 MW of solar generation at WPL. Estimated capital expenditures for the planned solar projects for 2021 through 2023 are included in the “Renewable projects” line in the construction and acquisitions table in “Liquidity and Capital Resources.”

Financings and Common Stock Dividends:

• | In April 2019, IPL issued $300 million of 3.60% senior debentures due 2029. In September 2019, IPL issued $300 million of 3.50% senior debentures due 2049. The senior debentures were issued as green bonds, and all of the net proceeds have been or will be allocated for the construction and development of IPL’s wind projects.

• | In June 2019, WPL issued $350 million of 3.00% debentures due 2029. The net proceeds from the issuance were used by WPL to reduce its outstanding commercial paper and retire its $250 million 5% debentures that matured in July 2019.

• | Refer to “Results of Operations” for discussion of expected issuances of common stock and long-term debt in 2020.

RESULTS OF OPERATIONS
Results of operations include financial information prepared in accordance with GAAP as well as utility electric margins and utility gas margins, which are not measures of financial performance under GAAP. Utility electric margins are defined as electric revenues less electric production fuel, purchased power and electric transmission service expenses. Utility gas margins are defined as gas revenues less cost of gas sold. Utility electric margins and utility gas margins are non-GAAP financial measures because they exclude other utility and non-utility revenues, other operation and maintenance expenses, depreciation and amortization expenses, and taxes other than income tax expense.
Management believes that utility electric and gas margins provide a meaningful basis for evaluating and managing utility operations since electric production fuel, purchased power and electric transmission service expenses and cost of gas sold are generally passed through to customers, and therefore, result in changes to electric and gas revenues that are comparable to changes in such expenses. The presentation of utility electric and gas margins herein is intended to provide supplemental information for investors regarding operating performance. These utility electric and gas margins may not be comparable to how other entities define utility electric and gas margin. Furthermore, these measures are not intended to replace operating income as determined in accordance with GAAP as an indicator of operating performance.
Additionally, the table below includes EPS for Utilities and Corporate Services, ATC Holdings, and Non-utility and Parent, which are non-GAAP financial measures. Alliant Energy believes these non-GAAP financial measures are useful to investors because they facilitate an understanding of segment performance and trends, and provide additional information about Alliant Energy’s operations on a basis consistent with the measures that management uses to manage its operations and evaluate its performance.
Financial Results Overview - Alliant Energy’s net income and EPS attributable to Alliant Energy common shareowners for the three months ended September 30, 2019 and 2018 were as follows (dollars in millions, except per share amounts):

| 2019 |  | 2018
| Income (Loss) |  | EPS |  | Income (Loss) |  | EPS
Utilities and Corporate Services |  | $219.6 |  |  |  | $0.92 |  |  |  | $206.3 |  |  |  | $0.88 |
ATC Holdings | 7.9 |  |  | 0.03 |  |  | 6.3 |  |  | 0.03 |
Non-utility and Parent | (1.5 | ) |  | (0.01 | ) |  | (7.1 | ) |  | (0.04 | )
Alliant Energy Consolidated |  | $226.0 |  |  |  | $0.94 |  |  |  | $205.5 |  |  |  | $0.87 |

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Alliant Energy’s Utilities and Corporate Services net income increased by $13 million for the three-month period, primarily due to higher earnings resulting from IPL’s and WPL’s increasing rate base and timing of income tax expense. These items were partially offset by higher depreciation expense.
For the three and nine months ended September 30, operating income and a reconciliation of utility electric and gas margins to the most directly comparable GAAP measure, operating income, was as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
Three Months | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Operating income |  | $290.2 |  |  |  | $256.1 |  |  |  | $173.5 |  |  |  | $143.1 |  |  |  | $108.3 |  |  |  | $104.2 |
Electric utility revenues |  | $915.9 |  |  |  | $861.2 |  |  |  | $560.9 |  |  |  | $509.2 |  |  |  | $355.0 |  |  |  | $352.0 |
Electric production fuel and purchased power expenses | (218.5 | ) |  | (227.8 | ) |  | (126.8 | ) |  | (122.5 | ) |  | (91.7 | ) |  | (105.3 | )
Electric transmission service expense | (127.5 | ) |  | (129.1 | ) |  | (91.8 | ) |  | (92.8 | ) |  | (35.7 | ) |  | (36.3 | )
Utility Electric Margin (non-GAAP) | 569.9 |  |  | 504.3 |  |  | 342.3 |  |  | 293.9 |  |  | 227.6 |  |  | 210.4 |
Gas utility revenues | 41.5 |  |  | 44.8 |  |  | 24.8 |  |  | 26.7 |  |  | 16.7 |  |  | 18.1 |
Cost of gas sold | (9.1 | ) |  | (11.3 | ) |  | (5.9 | ) |  | (6.4 | ) |  | (3.2 | ) |  | (4.9 | )
Utility Gas Margin (non-GAAP) | 32.4 |  |  | 33.5 |  |  | 18.9 |  |  | 20.3 |  |  | 13.5 |  |  | 13.2 |
Other utility revenues | 11.2 |  |  | 12.3 |  |  | 10.8 |  |  | 11.7 |  |  | 0.4 |  |  | 0.6 |
Non-utility revenues | 21.6 |  |  | 10.3 |  |  | — |  |  | — |  |  | — |  |  | — |
Other operation and maintenance expenses | (173.7 | ) |  | (148.4 | ) |  | (100.2 | ) |  | (94.6 | ) |  | (62.3 | ) |  | (54.2 | )
Depreciation and amortization expenses | (143.8 | ) |  | (129.0 | ) |  | (83.7 | ) |  | (73.9 | ) |  | (58.9 | ) |  | (54.1 | )
Taxes other than income tax expense | (27.4 | ) |  | (26.9 | ) |  | (14.6 | ) |  | (14.3 | ) |  | (12.0 | ) |  | (11.7 | )
Operating income |  | $290.2 |  |  |  | $256.1 |  |  |  | $173.5 |  |  |  | $143.1 |  |  |  | $108.3 |  |  |  | $104.2 |

| Alliant Energy |  | IPL |  | WPL
Nine Months | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Operating income |  | $616.8 |  |  |  | $573.0 |  |  |  | $321.5 |  |  |  | $296.4 |  |  |  | $273.4 |  |  |  | $251.6 |
Electric utility revenues |  | $2,350.5 |  |  |  | $2,296.2 |  |  |  | $1,373.0 |  |  |  | $1,337.0 |  |  |  | $977.5 |  |  |  | $959.2 |
Electric production fuel and purchased power expenses | (601.7 | ) |  | (639.5 | ) |  | (339.0 | ) |  | (354.0 | ) |  | (262.7 | ) |  | (285.5 | )
Electric transmission service expense | (362.9 | ) |  | (375.2 | ) |  | (256.9 | ) |  | (268.0 | ) |  | (106.0 | ) |  | (107.2 | )
Utility Electric Margin (non-GAAP) | 1,385.9 |  |  | 1,281.5 |  |  | 777.1 |  |  | 715.0 |  |  | 608.8 |  |  | 566.5 |
Gas utility revenues | 322.5 |  |  | 299.0 |  |  | 187.8 |  |  | 177.0 |  |  | 134.7 |  |  | 122.0 |
Cost of gas sold | (151.1 | ) |  | (150.0 | ) |  | (80.0 | ) |  | (83.8 | ) |  | (71.1 | ) |  | (66.2 | )
Utility Gas Margin (non-GAAP) | 171.4 |  |  | 149.0 |  |  | 107.8 |  |  | 93.2 |  |  | 63.6 |  |  | 55.8 |
Other utility revenues | 33.2 |  |  | 36.2 |  |  | 32.0 |  |  | 34.2 |  |  | 1.2 |  |  | 2.0 |
Non-utility revenues | 61.4 |  |  | 29.6 |  |  | — |  |  | — |  |  | — |  |  | — |
Other operation and maintenance expenses | (527.2 | ) |  | (468.8 | ) |  | (305.6 | ) |  | (297.1 | ) |  | (188.2 | ) |  | (172.8 | )
Depreciation and amortization expenses | (423.6 | ) |  | (376.4 | ) |  | (243.4 | ) |  | (209.2 | ) |  | (176.6 | ) |  | (164.2 | )
Taxes other than income tax expense | (84.3 | ) |  | (78.1 | ) |  | (46.4 | ) |  | (39.7 | ) |  | (35.4 | ) |  | (35.7 | )
Operating income |  | $616.8 |  |  |  | $573.0 |  |  |  | $321.5 |  |  |  | $296.4 |  |  |  | $273.4 |  |  |  | $251.6 |

Operating Income Variances - Variances between periods in operating income for the three and nine months ended September 30, 2019 compared to the same periods in 2018 were as follows (in millions):

| Three Months |  | Nine Months
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Total higher utility electric margin variance (Refer to details below) |  | $66 |  |  |  | $48 |  |  |  | $17 |  |  |  | $104 |  |  |  | $62 |  |  |  | $42 |
Total higher (lower) utility gas margin variance (Refer to details below) | (1 | ) |  | (1 | ) |  | — |  |  | 22 |  |  | 15 |  |  | 8 |
Higher non-utility revenues due to AEF’s new acquisitions | 10 |  |  | — |  |  | — |  |  | 31 |  |  | — |  |  | — |
Total higher other operation and maintenance expenses variance (Refer to details below) | (25 | ) |  | (6 | ) |  | (8 | ) |  | (58 | ) |  | (9 | ) |  | (15 | )
Higher depreciation and amortization expense, primarily due to additional plant in service in 2018 and 2019 and new IPL depreciation rates effective May 2018 | (15 | ) |  | (10 | ) |  | (5 | ) |  | (47 | ) |  | (34 | ) |  | (12 | )
Other | (1 | ) |  | (1 | ) |  | — |  |  | (8 | ) |  | (9 | ) |  | (1 | )
|  | $34 |  |  |  | $30 |  |  |  | $4 |  |  |  | $44 |  |  |  | $25 |  |  |  | $22 |

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Electric and Gas Revenues and Sales Summary - Electric and gas revenues (in millions), and MWh and Dth sales (in thousands), for the three and nine months ended September 30 were as follows:

Alliant Energy | Electric |  | Gas
| Revenues |  | MWhs Sold |  | Revenues |  | Dths Sold
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Three Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail |  | $825.9 |  |  |  | $776.1 |  |  | 6,868 |  |  | 6,892 |  |  |  | $32.7 |  |  |  | $35.8 |  |  | 3,144 |  |  | 3,867 |
Sales for resale | 71.9 |  |  | 70.2 |  |  | 2,003 |  |  | 1,675 |  |  | N/A |  |  | N/A |  |  | N/A |  |  | N/A |
Transportation/Other | 18.1 |  |  | 14.9 |  |  | 23 |  |  | 19 |  |  | 8.8 |  |  | 9.0 |  |  | 25,021 |  |  | 23,213 |
|  | $915.9 |  |  |  | $861.2 |  |  | 8,894 |  |  | 8,586 |  |  |  | $41.5 |  |  |  | $44.8 |  |  | 28,165 |  |  | 27,080 |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail |  | $2,109.2 |  |  |  | $2,057.4 |  |  | 19,035 |  |  | 19,399 |  |  |  | $286.8 |  |  |  | $268.8 |  |  | 36,560 |  |  | 35,678 |
Sales for resale | 191.0 |  |  | 198.8 |  |  | 4,835 |  |  | 4,557 |  |  | N/A |  |  | N/A |  |  | N/A |  |  | N/A |
Transportation/Other | 50.3 |  |  | 40.0 |  |  | 71 |  |  | 67 |  |  | 35.7 |  |  | 30.2 |  |  | 71,814 |  |  | 67,886 |
|  | $2,350.5 |  |  |  | $2,296.2 |  |  | 23,941 |  |  | 24,023 |  |  |  | $322.5 |  |  |  | $299.0 |  |  | 108,374 |  |  | 103,564 |

IPL | Electric |  | Gas
| Revenues |  | MWhs Sold |  | Revenues |  | Dths Sold
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Three Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail |  | $511.9 |  |  |  | $467.5 |  |  | 3,827 |  |  | 3,838 |  |  |  | $19.5 |  |  |  | $21.0 |  |  | 1,644 |  |  | 2,060 |
Sales for resale | 37.8 |  |  | 31.0 |  |  | 1,414 |  |  | 917 |  |  | N/A |  |  | N/A |  |  | N/A |  |  | N/A |
Transportation/Other | 11.2 |  |  | 10.7 |  |  | 9 |  |  | 10 |  |  | 5.3 |  |  | 5.7 |  |  | 8,701 |  |  | 8,994 |
|  | $560.9 |  |  |  | $509.2 |  |  | 5,250 |  |  | 4,765 |  |  |  | $24.8 |  |  |  | $26.7 |  |  | 10,345 |  |  | 11,054 |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail |  | $1,247.8 |  |  |  | $1,218.4 |  |  | 10,706 |  |  | 11,060 |  |  |  | $165.8 |  |  |  | $156.8 |  |  | 19,010 |  |  | 18,838 |
Sales for resale | 95.7 |  |  | 91.6 |  |  | 3,241 |  |  | 2,444 |  |  | N/A |  |  | N/A |  |  | N/A |  |  | N/A |
Transportation/Other | 29.5 |  |  | 27.0 |  |  | 27 |  |  | 28 |  |  | 22.0 |  |  | 20.2 |  |  | 28,528 |  |  | 28,893 |
|  | $1,373.0 |  |  |  | $1,337.0 |  |  | 13,974 |  |  | 13,532 |  |  |  | $187.8 |  |  |  | $177.0 |  |  | 47,538 |  |  | 47,731 |

WPL | Electric |  | Gas
| Revenues |  | MWhs Sold |  | Revenues |  | Dths Sold
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Three Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail |  | $314.0 |  |  |  | $308.6 |  |  | 3,041 |  |  | 3,054 |  |  |  | $13.2 |  |  |  | $14.8 |  |  | 1,500 |  |  | 1,807 |
Sales for resale | 34.1 |  |  | 39.2 |  |  | 589 |  |  | 758 |  |  | N/A |  |  | N/A |  |  | N/A |  |  | N/A |
Transportation/Other | 6.9 |  |  | 4.2 |  |  | 14 |  |  | 9 |  |  | 3.5 |  |  | 3.3 |  |  | 16,320 |  |  | 14,219 |
|  | $355.0 |  |  |  | $352.0 |  |  | 3,644 |  |  | 3,821 |  |  |  | $16.7 |  |  |  | $18.1 |  |  | 17,820 |  |  | 16,026 |
Nine Months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retail |  | $861.4 |  |  |  | $839.0 |  |  | 8,329 |  |  | 8,339 |  |  |  | $121.0 |  |  |  | $112.0 |  |  | 17,550 |  |  | 16,840 |
Sales for resale | 95.3 |  |  | 107.2 |  |  | 1,594 |  |  | 2,113 |  |  | N/A |  |  | N/A |  |  | N/A |  |  | N/A |
Transportation/Other | 20.8 |  |  | 13.0 |  |  | 44 |  |  | 39 |  |  | 13.7 |  |  |  | $10.0 |  |  | 43,286 |  |  | 38,993 |
|  | $977.5 |  |  |  | $959.2 |  |  | 9,967 |  |  | 10,491 |  |  |  | $134.7 |  |  |  | $122.0 |  |  | 60,836 |  |  | 55,833 |

Sales Trends and Temperatures - Alliant Energy’s retail electric sales volumes remained unchanged and decreased 2% for the three and nine months ended September 30, 2019 compared to the same periods in 2018, respectively. The decrease for the nine-month period was primarily due to the impact of lower residential and commercial sales due to cooler temperatures during the second quarter of 2019.
Estimated increases to electric and gas margins from the impacts of temperatures for the three and nine months ended September 30 were as follows (in millions):

| Electric Margins |  | Gas Margins
| Three Months |  | Nine Months |  | Three Months |  | Nine Months
| 2019 |  | 2018 |  | Change |  | 2019 |  | 2018 |  | Change |  | 2019 |  | 2018 |  | Change |  | 2019 |  | 2018 |  | Change
IPL |  | $4 |  |  |  | $4 |  |  |  | $— |  |  |  | $7 |  |  |  | $18 |  |  |  | ($11 | ) |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $4 |  |  |  | $1 |  |  |  | $3 |
WPL | 2 |  |  | 3 |  |  | (1 | ) |  | 2 |  |  | 10 |  |  | (8 | ) |  | — |  |  | — |  |  | — |  |  | 2 |  |  | 1 |  |  | 1 |
Total Alliant Energy |  | $6 |  |  |  | $7 |  |  |  | ($1 | ) |  |  | $9 |  |  |  | $28 |  |  |  | ($19 | ) |  |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $6 |  |  |  | $2 |  |  |  | $4 |

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Utility Electric Margin Variances - The following items contributed to increased (decreased) utility electric margins for the three and nine months ended September 30, 2019 compared to the same periods in 2018 as follows (in millions):

| Three Months |  | Nine Months
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Impact of IPL’s retail electric interim and final base rate increases effective April 2019 and May 2018, respectively (a) |  | $41 |  |  |  | $41 |  |  |  | $— |  |  |  | $77 |  |  |  | $77 |  |  |  | $— |
Higher margins at WPL from earning on increasing rate base for rates effective January 2019 | 16 |  |  | — |  |  | 16 |  |  | 42 |  |  | — |  |  | 42 |
Estimated changes in sales volumes caused by temperatures | (1 | ) |  | — |  |  | (1 | ) |  | (19 | ) |  | (11 | ) |  | (8 | )
Higher revenues at IPL due to changes in electric tax benefit rider credits on customers’ bills (offset by changes in income tax expense) | 6 |  |  | 6 |  |  | — |  |  | 4 |  |  | 4 |  |  | — |
Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense) | 2 |  |  | 2 |  |  | — |  |  | 3 |  |  | 3 |  |  |
Other | 2 |  |  | (1 | ) |  | 2 |  |  | (3 | ) |  | (11 | ) |  | 8 |
|  | $66 |  |  |  | $48 |  |  |  | $17 |  |  |  | $104 |  |  |  | $62 |  |  |  | $42 |

(a) | IPL’s interim retail electric base rate increase effective April 1, 2019 was reduced by anticipated production tax credits for IPL’s new wind generation placed in service in March 2019. This reduction in revenue requirement is expected to be offset by a reduction in income tax expense resulting from production tax credits recognized from the new wind generation. Additionally, the interim retail electric base rate increase was reduced by $8 million as a result of the partial refund agreed to as part of the rate review proposed settlement. Refer to Note 2 for further discussion.

Utility Gas Margin Variances - The following items contributed to increased (decreased) utility gas margins for the three and nine months ended September 30, 2019 compared to the same periods in 2018 as follows (in millions):

| Three Months |  | Nine Months
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Impact of IPL’s retail gas final base rate increase effective January 2019 |  | $— |  |  |  | $— |  |  |  | $— |  |  |  | $8 |  |  |  | $8 |  |  |  | $— |
Higher margins at WPL from earning on increasing rate base for rates effective January 2019 | 1 |  |  | — |  |  | 1 |  |  | 6 |  |  | — |  |  | 6 |
Estimated changes in sales volumes caused by temperatures | — |  |  | — |  |  | — |  |  | 4 |  |  | 3 |  |  | 1 |
Higher revenues at IPL related to changes in recovery amounts for energy efficiency costs through the energy efficiency rider (mostly offset by changes in energy efficiency expense) | — |  |  | — |  |  | — |  |  | 3 |  |  | 3 |  |  | — |
Other | (2 | ) |  | (1 | ) |  | (1 | ) |  | 1 |  |  | 1 |  |  | 1 |
|  | ($1 | ) |  |  | ($1 | ) |  |  | $— |  |  |  | $22 |  |  |  | $15 |  |  |  | $8 |

Other Operation and Maintenance Expenses Variances - The following items contributed to (increased) decreased other operation and maintenance expenses for the three and nine months ended September 30, 2019 compared to the same periods in 2018 as follows (in millions):

| Three Months |  | Nine Months
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Higher operation expense at AEF due to new acquisitions |  | ($10 | ) |  |  | $— |  |  |  | $— |  |  |  | ($29 | ) |  |  | $— |  |  |  | $— |
Higher energy efficiency cost recovery amortizations at WPL pursuant to authorization from PSCW rate order effective January 2019 | (4 | ) |  | — |  |  | (4 | ) |  | (11 | ) |  | — |  |  | (11 | )
Higher energy efficiency expense at IPL (primarily offset by higher gas revenues) | (1 | ) |  | (1 | ) |  | — |  |  | (5 | ) |  | (5 | ) |  | — |
Higher performance compensation expense | (4 | ) |  | (2 | ) |  | (2 | ) |  | (5 | ) |  | (2 | ) |  | (2 | )
Other | (6 | ) |  | (3 | ) |  | (2 | ) |  | (8 | ) |  | (2 | ) |  | (2 | )
|  | ($25 | ) |  |  | ($6 | ) |  |  | ($8 | ) |  |  | ($58 | ) |  |  | ($9 | ) |  |  | ($15 | )

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Other Income and Deductions Variances - The following items contributed to (increased) decreased other income and deductions for the three and nine months ended September 30, 2019 compared to the same periods in 2018 as follows (in millions):

| Three Months |  | Nine Months
| Alliant Energy |  | IPL |  | WPL |  | Alliant Energy |  | IPL |  | WPL
Higher interest expense primarily due to higher average outstanding long-term debt balances |  | ($5 | ) |  |  | ($1 | ) |  |  | ($1 | ) |  |  | ($20 | ) |  |  | ($2 | ) |  |  | ($4 | )
Lower equity income due to decreased earnings from non-utility wind farm resulting from an acceleration of earnings in the first quarter of 2018 due to Federal Tax Reform | — |  |  | — |  |  | — |  |  | (12 | ) |  | — |  |  | — |
Higher allowance for funds used during construction primarily due to changes in construction work in progress balances related to IPL’s new wind generation and WPL’s West Riverside Energy Center | 3 |  |  | — |  |  | 3 |  |  | 14 |  |  | 6 |  |  | 8 |
Other | — |  |  | (2 | ) |  | — |  |  | — |  |  | (3 | ) |  | (1 | )
|  | ($2 | ) |  |  | ($3 | ) |  |  | $2 |  |  |  | ($18 | ) |  |  | $1 |  |  |  | $3 |

Income Taxes - Refer to Note 9 for details of effective income tax rates.
Other Future Considerations - In addition to items discussed in MDA and the Notes in Item 1, the following key items could impact Alliant Energy’s, IPL’s and WPL’s future financial condition or results of operations:

• | Financing Plans - Alliant Energy currently expects to issue up to $250 million of common stock in 2020 through one or more offerings and its Shareowner Direct Plan. IPL, WPL and AEF currently expect to issue up to $300 million, $350 million and $300 million of long-term debt in 2020, respectively. IPL, WPL and AEF have $200 million, $150 million and $300 million of long-term debt maturing in 2020, respectively.

• | Common Stock Dividends - Alliant Energy announced a 7% increase in its targeted 2020 annual common stock dividend to $1.52 per share, which is equivalent to a quarterly rate of $0.38 per share, beginning with the February 2020 dividend payment. The timing and amount of future dividends is subject to an approved dividend declaration from Alliant Energy’s Board of Directors, and is dependent upon earnings expectations, capital requirements, and general financial business conditions, among other factors.

• | Higher Earnings on Increasing Rate Base - Alliant Energy and IPL currently expect an increase in earnings in 2020 compared to 2019 due to impacts from increasing revenue requirements from IPL’s retail electric and gas rate reviews (2020 Forward-looking Test Period). IPL’s and WPL’s 2020 increased revenue requirements are expected to be offset by returning to customers a portion of the excess deferred income tax credits from Federal Tax Reform.

• | Depreciation and Amortization Expenses - Alliant Energy, IPL and WPL currently expect an increase in depreciation and amortization expenses in 2020 compared to 2019 due to property additions, including IPL’s expansion of wind generation and WPL’s West Riverside natural gas-fired EGU.

• | Interest Expense - Alliant Energy currently expects interest expense to increase in 2020 compared to 2019 primarily due to financings completed in 2019 and planned in 2020 as discussed above.

• | Allowance for Funds Used During Construction - Alliant Energy currently expects allowance for funds used during construction to decrease in 2020 compared to 2019 primarily due to decreased construction work in progress balances related to IPL’s wind generation that was placed in service in 2019 and is expected to be placed in service in 2020, and WPL’s West Riverside Energy Center, which is currently expected to be placed in service by the end of 2019.

LIQUIDITY AND CAPITAL RESOURCES
The liquidity and capital resources summary included in the 2018 Form 10-K has not changed materially, except as described below.
Liquidity Position - At September 30, 2019, Alliant Energy had $194 million of cash and cash equivalents, $650 million ($100 million at the parent company, $250 million at IPL and $300 million at WPL) of available capacity under the single revolving credit facility and $109 million of available capacity at IPL under its sales of accounts receivable program.

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Capital Structure - Capital structures at September 30, 2019 were as follows (Long-term Debt (including current maturities) (LD); Short-term Debt (SD); Common Equity (CE); IPL’s Preferred Stock (PS)):
Cash Flows - Selected information from the cash flows statements was as follows (in millions):

| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Cash, cash equivalents and restricted cash, January 1 |  | $25.5 |  |  |  | $33.9 |  |  |  | $12.4 |  |  |  | $7.2 |  |  |  | $9.2 |  |  |  | $24.2 |
Cash flows from (used for): |  |  |  |  |  |  |  |  |  |  |
Operating activities | 509.2 |  |  | 442.2 |  |  | 138.5 |  |  | 38.9 |  |  | 359.6 |  |  | 345.5 |
Investing activities | (861.1 | ) |  | (815.7 | ) |  | (484.1 | ) |  | (328.9 | ) |  | (334.9 | ) |  | (468.7 | )
Financing activities | 526.1 |  |  | 587.4 |  |  | 518.5 |  |  | 519.1 |  |  | (24.3 | ) |  | 106.7 |
Net increase (decrease) | 174.2 |  |  | 213.9 |  |  | 172.9 |  |  | 229.1 |  |  | 0.4 |  |  | (16.5 | )
Cash, cash equivalents and restricted cash, September 30 |  | $199.7 |  |  |  | $247.8 |  |  |  | $185.3 |  |  |  | $236.3 |  |  |  | $9.6 |  |  |  | $7.7 |

Operating Activities - The following items contributed to increased (decreased) operating activity cash flows for the nine months ended September 30, 2019 compared to the same period in 2018 (in millions):

| Alliant Energy |  | IPL |  | WPL
Higher collections from IPL’s retail electric and gas base rate increases |  | $84 |  |  |  | $84 |  |  |  | $— |
Changes in amounts refunded to customers related to Federal Tax Reform | 35 |  |  | 6 |  |  | 29 |
Changes in income taxes paid/refunded | 6 |  |  | 11 |  |  | 4 |
Contributions to qualified defined benefit pension plans in 2019 | (24 | ) |  | (12 | ) |  | (12 | )
Changes in interest payments | (23 | ) |  | (5 | ) |  | (5 | )
Changes in levels of production fuel | (20 | ) |  | (5 | ) |  | (15 | )
Decreased collections from IPL’s and WPL’s retail customers caused by temperature impacts on electric and gas sales | (15 | ) |  | (8 | ) |  | (7 | )
Timing of intercompany payments and receipts | — |  |  | 19 |  |  | 1 |
Other | 24 |  |  | 10 |  |  | 19 |
|  | $67 |  |  |  | $100 |  |  |  | $14 |

Investing Activities - The following items contributed to increased (decreased) investing activity cash flows for the nine months ended September 30, 2019 compared to the same period in 2018 (in millions):

| Alliant Energy |  | IPL |  | WPL
Changes in the amount of cash receipts on sold receivables |  | ($81 | ) |  |  | ($81 | ) |  |  | $— |
Lower (higher) utility construction and acquisition expenditures (a) | 76 |  |  | (61 | ) |  | 137 |
Other | (40 | ) |  | (13 | ) |  | (3 | )
|  | ($45 | ) |  |  | ($155 | ) |  |  | $134 |

(a) | Largely due to lower WPL expenditures related to the acquisition of a partial interest in the Forward Wind Energy Center in 2018 and lower expenditures for the West Riverside Energy Center, partially offset by higher IPL expenditures related to its expansion of wind generation.

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Construction and Acquisition Expenditures - Construction and acquisition expenditures for 2019 through 2023 are currently anticipated as follows (in millions). Cost estimates represent Alliant Energy’s, IPL’s and WPL’s portion of construction expenditures and exclude allowance for funds used during construction and capitalized interest, if applicable. Such amounts do not include IPL’s expected $110 million buyout payment in September 2020 related to the DAEC PPA. Such estimates reflect reductions to Alliant Energy’s and WPL’s capital expenditures resulting from purchase options by certain electric cooperatives for a partial ownership interest in the West Riverside Energy Center; however, such estimates do not reflect any potential proceeds if neighboring utilities exercise options for a partial ownership in the West Riverside Energy Center.

| Alliant Energy |  | IPL |  | WPL
| 2019 | 2020 | 2021 | 2022 | 2023 |  | 2019 | 2020 | 2021 | 2022 | 2023 |  | 2019 | 2020 | 2021 | 2022 | 2023
Generation: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Renewable projects |  | $640 |  |  | $260 |  |  | $110 |  |  | $275 |  |  | $390 |  |  |  | $525 |  |  | $135 |  |  | $— |  |  | $— |  |  | $— |  |  |  | $115 |  |  | $125 |  |  | $110 |  |  | $275 |  |  | $390 |
West Riverside | 80 |  | 15 |  | — |  | — |  | — |  |  | — |  | — |  | — |  | — |  | — |  |  | 80 |  | 15 |  | — |  | — |  | — |
Other | 105 |  | 190 |  | 140 |  | 170 |  | 90 |  |  | 55 |  | 90 |  | 85 |  | 125 |  | 50 |  |  | 50 |  | 100 |  | 55 |  | 45 |  | 40 |
Distribution: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Electric systems | 450 |  | 570 |  | 535 |  | 525 |  | 540 |  |  | 270 |  | 320 |  | 285 |  | 270 |  | 310 |  |  | 180 |  | 250 |  | 250 |  | 255 |  | 230 |
Gas systems | 95 |  | 185 |  | 80 |  | 130 |  | 105 |  |  | 50 |  | 50 |  | 45 |  | 95 |  | 65 |  |  | 45 |  | 135 |  | 35 |  | 35 |  | 40 |
Other | 150 |  | 205 |  | 180 |  | 235 |  | 245 |  |  | 20 |  | 30 |  | 10 |  | 10 |  | 15 |  |  | 15 |  | 15 |  | 10 |  | 20 |  | 15 |
|  | $1,520 |  |  | $1,425 |  |  | $1,045 |  |  | $1,335 |  |  | $1,370 |  |  |  | $920 |  |  | $625 |  |  | $425 |  |  | $500 |  |  | $440 |  |  |  | $485 |  |  | $640 |  |  | $460 |  |  | $630 |  |  | $715 |

Financing Activities - The following items contributed to increased (decreased) financing activity cash flows for the nine months ended September 30, 2019 compared to the same period in 2018 (in millions):

| Alliant Energy |  | IPL |  | WPL
Lower (higher) payments to retire long-term debt |  | $350 |  |  |  | $100 |  |  |  | ($250 | )
Net changes in the amount of commercial paper and other short-term borrowings outstanding | 187 |  |  | (50 | ) |  | (119 | )
Higher (lower) net proceeds from issuance of long-term debt | (550 | ) |  | 100 |  |  | 350 |
Lower capital contributions from IPL’s and WPL’s parent company, Alliant Energy | — |  |  | (130 | ) |  | (100 | )
Other | (48 | ) |  | (21 | ) |  | (12 | )
|  | ($61 | ) |  |  | ($1 | ) |  |  | ($131 | )

State Regulatory Financing Authorizations - In October 2019, WPL received authorization from the PSCW to issue up to $350 million of long-term debt securities in aggregate in 2020.
Common Stock Issuances and Common Stock Dividends - Refer to Note 5 for discussion of common stock issuances by Alliant Energy in 2019. Refer to “Results of Operations” for discussion of expected issuances of common stock and common stock dividends in 2020.
Short- and Long-term Debt - Refer to Note 6 for discussion of amendments to the single credit facility agreement in March 2019, and IPL’s and WPL’s issuances of long-term debt in 2019. Refer to “Results of Operations” for discussion of expected issuances of long-term debt in 2020.
Off-Balance Sheet Arrangements - A summary of Alliant Energy’s off-balance sheet arrangements is included in the 2018 Form 10-K and has not changed materially from the items reported in the 2018 Form 10-K, except for the items described in Note 3.
Certain Financial Commitments -
Contractual Obligations - A summary of Alliant Energy’s, IPL’s and WPL’s contractual obligations is included in the 2018 Form 10-K and has not changed materially from the items reported in the 2018 Form 10-K, except for the items described in Notes 6, 7 and 14.

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OTHER MATTERS
Critical Accounting Policies and Estimates - The summary of critical accounting policies and estimates included in the 2018 Form 10-K has not changed materially, except as described below.
Long-Lived Assets -
Regulated Operations -
Assets Subject to Early Retirement - Upon completion of the phased installation of an advanced metering infrastructure program, IPL retired certain analog electric meters in September 2019. IPL’s retail electric rate review settlement, described in Note 2, includes recovery of the remaining net book value of these meters from IPL’s retail customers. However, the settlement does not allow IPL to earn a return on the remaining net book value when final rates are implemented, and as a result, Alliant Energy and IPL recorded a $4 million write-down of regulatory assets in the third quarter of 2019.
ITEM 3. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK
Quantitative and Qualitative Disclosures About Market Risk are reported in the 2018 Form 10-K and have not changed materially.
ITEM 4. CONTROLS AND PROCEDURES
Alliant Energy’s, IPL’s and WPL’s management evaluated, with the participation of each of Alliant Energy’s, IPL’s and WPL’s Chief Executive Officer, Chief Financial Officer and Disclosure Committee, the effectiveness of the design and operation of Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures (as defined in Rule 13a-15(e) of the Securities Exchange Act of 1934) as of September 30, 2019 pursuant to the requirements of the Securities Exchange Act of 1934, as amended. Based on their evaluation, the Chief Executive Officer and the Chief Financial Officer concluded that Alliant Energy’s, IPL’s and WPL’s disclosure controls and procedures were effective as of the quarter ended September 30, 2019.
There was no change in Alliant Energy’s, IPL’s and WPL’s internal control over financial reporting that occurred during the quarter ended September 30, 2019 that has materially affected, or is reasonably likely to materially affect, Alliant Energy’s, IPL’s or WPL’s internal control over financial reporting.
PART II. OTHER INFORMATION
ITEM 1A. RISK FACTORS
The risk factors described in Item 1A in the 2018 Form 10-K have not changed materially.
ITEM 2. UNREGISTERED SALES OF EQUITY SECURITIES AND USE OF PROCEEDS
A summary of Alliant Energy common stock repurchases for the quarter ended September 30, 2019 was as follows:

|  | Total Number |  | Average Price |  | Total Number of Shares |  | Maximum Number (or Approximate
|  | of Shares |  | Paid Per |  | Purchased as Part of |  | Dollar Value) of Shares That May
Period |  | Purchased (a) |  | Share |  | Publicly Announced Plan |  | Yet Be Purchased Under the Plan (a)
July 1 through July 31 |  | 1,895 |  |  |  | $50.25 |  |  | — |  | N/A
August 1 through August 31 |  | 2,803 |  |  | 51.57 |  |  | — |  | N/A
September 1 through September 30 |  | 165 |  |  | 52.72 |  |  | — |  | N/A
|  | 4,863 |  |  | 51.09 |  |  | — |  |

(a) | All shares were purchased on the open market and held in a rabbi trust under the Alliant Energy Deferred Compensation Plan. There is no limit on the number of shares of Alliant Energy common stock that may be held under the Deferred Compensation Plan, which currently does not have an expiration date.

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Table of Contents
ITEM 6. EXHIBITS
The following Exhibits are filed herewith or incorporated herein by reference.

Exhibit Number |  | Description
4.1 |  | Officer’s Certificate, dated as of September 26, 2019, creating IPL’s 3.50% Senior Debentures due September 30, 2049 (incorporated by reference to Exhibit 4.1 to IPL’s Form 8-K, filed September 26, 2019 (File No. 1-4117))
31.1 |  | Certification of the Chief Executive Officer for Alliant Energy
31.2 |  | Certification of the Chief Financial Officer for Alliant Energy
31.3 |  | Certification of the Chief Executive Officer for IPL
31.4 |  | Certification of the Chief Financial Officer for IPL
31.5 |  | Certification of the Chief Executive Officer for WPL
31.6 |  | Certification of the Chief Financial Officer for WPL
32.1 |  | Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for Alliant Energy
32.2 |  | Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for IPL
32.3 |  | Written Statement of the Chief Executive Officer and Chief Financial Officer Pursuant to 18 U.S.C.§1350 for WPL
101.INS |  | Inline XBRL Instance Document - the instance document does not appear in the Interactive Data File because its XBRL tags are embedded within the Inline XBRL document
101.SCH |  | Inline XBRL Taxonomy Extension Schema Document
101.CAL |  | Inline XBRL Taxonomy Extension Calculation Linkbase Document
101.LAB |  | Inline XBRL Taxonomy Extension Label Linkbase Document
101.PRE |  | Inline XBRL Taxonomy Extension Presentation Linkbase Document
101.DEF |  | Inline XBRL Taxonomy Extension Definition Linkbase Document
104 |  | Cover Page Interactive Data File (embedded within the Inline XBRL document)

SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, Alliant Energy Corporation, Interstate Power and Light Company and Wisconsin Power and Light Company have each duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized on the 7th day of November 2019.

ALLIANT ENERGY CORPORATION |
Registrant |
By: /s/ Benjamin M. Bilitz | Chief Accounting Officer and Controller
Benjamin M. Bilitz | (Principal Accounting Officer and Authorized Signatory)

INTERSTATE POWER AND LIGHT COMPANY |
Registrant |
By: /s/ Benjamin M. Bilitz | Chief Accounting Officer and Controller
Benjamin M. Bilitz | (Principal Accounting Officer and Authorized Signatory)

WISCONSIN POWER AND LIGHT COMPANY |
Registrant |
By: /s/ Benjamin M. Bilitz | Chief Accounting Officer and Controller
Benjamin M. Bilitz | (Principal Accounting Officer and Authorized Signatory)

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