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Employee Benefit Plans | 12 Months Ended
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Dec. 31, 2018
Retirement Benefits [Abstract] |
Employee Benefit Plans | EMPLOYEE BENEFIT PLANS DEFINED BENEFIT RETIREMENT PLANS Duke Energy and certain subsidiaries maintain, and the Subsidiary Registrants participate in, qualified, non-contributory defined benefit retirement plans. The Duke Energy plans cover most employees using a cash balance formula. Under a cash balance formula, a plan participant accumulates a retirement benefit consisting of pay credits based upon a percentage of current eligible earnings, age or age and years of service and interest credits. Certain employees are eligible for benefits that use a final average earnings formula. Under these final average earnings formulas, a plan participant accumulates a retirement benefit equal to the sum of percentages of their (i) highest three-year, four-year, or five-year average earnings, (ii) highest three-year, four-year, or five-year average earnings in excess of covered compensation per year of participation (maximum of 35 years) or (iii) highest three-year average earnings times years of participation in excess of 35 years. Duke Energy also maintains, and the Subsidiary Registrants participate in, non-qualified, non-contributory defined benefit retirement plans that cover certain executives. The qualified and non-qualified, non-contributory defined benefit plans are closed to new participants. Duke Energy approved plan amendments to restructure its qualified non-contributory defined benefit retirement plans, effective January 1, 2018. The restructuring involved (i) the spin-off of the majority of inactive participants from two plans into a separate inactive plan and (ii) the merger of the active participant portions of such plans, along with a pension plan acquired as part of the Piedmont transaction, into a single active plan. Benefits offered to the plan participants remain unchanged except that the Piedmont plan's final average earnings formula was frozen as of December 31, 2017, and affected participants were moved into the active plan's cash balance formula. Actuarial gains and losses associated with the Inactive Plan will be amortized over the remaining life expectancy of the inactive participants. The longer amortization period lowered Duke Energy's 2018 pretax qualified pension plan expense by approximately $33 million. Duke Energy uses a December 31 measurement date for its defined benefit retirement plan assets and obligations. Net periodic benefit costs disclosed in the tables below represent the cost of the respective benefit plan for the periods presented prior to capitalization of amounts reflected as Net property, plant and equipment, on the Consolidated Balance Sheets. Only the service cost component of net periodic benefit costs is eligible to be capitalized. The remaining non-capitalized portions of net periodic benefit costs are classified as either: (1) service cost, which is recorded in Operations, maintenance and other on the Consolidated Statements of Operations; or as (2) components of non-service cost, which is recorded in Other income and expenses, net, on the Consolidated Statements of Operations. Amounts presented in the tables below for the Subsidiary Registrants represent the amounts of pension and other post-retirement benefit cost allocated by Duke Energy for employees of the Subsidiary Registrants. Additionally, the Consolidated Statements of Operations of the Subsidiary Registrants also include allocated net periodic benefit costs for their proportionate share of pension and post-retirement benefit cost for employees of Duke Energy’s shared services affiliate that provide support to the Subsidiary Registrants. However, in the tables below, these amounts are only presented within the Duke Energy column. These allocated amounts are included in the governance and shared service costs discussed in Note 13. Duke Energy’s policy is to fund amounts on an actuarial basis to provide assets sufficient to meet benefit payments to be paid to plan participants. Duke Energy does not anticipate making any contributions in 2019. The following table includes information related to the Duke Energy Registrants’ contributions to its qualified defined benefit pension plans.
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont(a) |
Contributions Made: |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 | $ | 141 |  |  | $ | 46 |  |  | $ | 45 |  |  | $ | 25 |  |  | $ | 20 |  |  | $ | — |  |  | $ | 8 |  |  | $ | — |
2017 | 19 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4 |  |  | — |  |  | 11 |
2016 | 155 |  |  | 43 |  |  | 43 |  |  | 24 |  |  | 20 |  |  | 5 |  |  | 9 |  |  |  |
(a) | Piedmont contributed $10 million to its U.S. qualified defined benefit pension plan during the two months ended December 31, 2016, and $10 million for the year ended October 31, 2016.
QUALIFIED PENSION PLANS Components of Net Periodic Pension Costs
| Year Ended December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Service cost | $ | 182 |  |  | $ | 58 |  |  | $ | 51 |  |  | $ | 29 |  |  | $ | 22 |  |  | $ | 5 |  |  | $ | 11 |  |  | $ | 7 |
Interest cost on projected benefit obligation | 299 |  |  | 72 |  |  | 94 |  |  | 43 |  |  | 50 |  |  | 17 |  |  | 23 |  |  | 11 |
Expected return on plan assets | (559 | ) |  | (147 | ) |  | (178 | ) |  | (85 | ) |  | (91 | ) |  | (28 | ) |  | (42 | ) |  | (22 | )
Amortization of actuarial loss | 132 |  |  | 29 |  |  | 44 |  |  | 21 |  |  | 23 |  |  | 5 |  |  | 10 |  |  | 11 |
Amortization of prior service credit | (32 | ) |  | (8 | ) |  | (3 | ) |  | (2 | ) |  | (1 | ) |  | — |  |  | (2 | ) |  | (10 | )
Net periodic pension costs(a)(b) | $ | 22 |  |  | $ | 4 |  |  | $ | 8 |  |  | $ | 6 |  |  | $ | 3 |  |  | $ | (1 | ) |  | $ | — |  |  | $ | (3 | )
| Year Ended December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Service cost | $ | 159 |  |  | $ | 48 |  |  | $ | 45 |  |  | $ | 26 |  |  | $ | 19 |  |  | $ | 4 |  |  | $ | 9 |  |  | $ | 10 |
Interest cost on projected benefit obligation | 328 |  |  | 79 |  |  | 100 |  |  | 47 |  |  | 53 |  |  | 18 |  |  | 26 |  |  | 14 |
Expected return on plan assets | (545 | ) |  | (142 | ) |  | (167 | ) |  | (82 | ) |  | (85 | ) |  | (27 | ) |  | (42 | ) |  | (24 | )
Amortization of actuarial loss | 146 |  |  | 31 |  |  | 52 |  |  | 23 |  |  | 29 |  |  | 5 |  |  | 12 |  |  | 11 |
Amortization of prior service credit | (24 | ) |  | (8 | ) |  | (3 | ) |  | (2 | ) |  | (1 | ) |  | (1 | ) |  | (2 | ) |  | (2 | )
Settlement charge | 12 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 12 |
Other | 8 |  |  | 2 |  |  | 2 |  |  | 1 |  |  | 1 |  |  | — |  |  | 1 |  |  | 1 |
Net periodic pension costs(a)(b) | $ | 84 |  |  | $ | 10 |  |  | $ | 29 |  |  | $ | 13 |  |  | $ | 16 |  |  | $ | (1 | ) |  | $ | 4 |  |  | $ | 22 |
| Year Ended December 31, 2016
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |
Service cost | $ | 147 |  |  | $ | 48 |  |  | $ | 42 |  |  | $ | 24 |  |  | $ | 19 |  |  | $ | 4 |  |  | $ | 9 |
Interest cost on projected benefit obligation | 335 |  |  | 86 |  |  | 106 |  |  | 49 |  |  | 55 |  |  | 19 |  |  | 28 |
Expected return on plan assets | (519 | ) |  | (142 | ) |  | (168 | ) |  | (82 | ) |  | (84 | ) |  | (27 | ) |  | (42 | )
Amortization of actuarial loss | 134 |  |  | 33 |  |  | 51 |  |  | 23 |  |  | 29 |  |  | 4 |  |  | 11 |
Amortization of prior service credit | (17 | ) |  | (8 | ) |  | (3 | ) |  | (2 | ) |  | (1 | ) |  | — |  |  | (1 | )
Settlement charge | 3 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Other | 8 |  |  | 2 |  |  | 3 |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |
Net periodic pension costs(a)(b) | $ | 91 |  |  | $ | 19 |  |  | $ | 31 |  |  | $ | 13 |  |  | $ | 19 |  |  | $ | 1 |  |  | $ | 6 |
(a) | Duke Energy amounts exclude $5 million, $7 million and $8 million for the years ended December 2018, 2017 and 2016, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006.
(b) | Duke Energy Ohio amounts exclude $2 million, $3 million and $4 million for the years ended December 2018, 2017 and 2016, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006.
| Piedmont
| Two Months Ended |  | Year Ended
(in millions) | December 31, 2016 |  | October 31, 2016
Service cost | $ | 2 |  |  | $ | 11 |
Interest cost on projected benefit obligation | 2 |  |  | 9 |
Expected return on plan assets | (4 | ) |  | (24 | )
Amortization of actuarial loss | 2 |  |  | 8 |
Amortization of prior service credit | (1 | ) |  | (2 | )
Settlement charge | 3 |  |  | — |
Net periodic pension costs | $ | 4 |  |  | $ | 2 |
Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets
| Year Ended December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Regulatory assets, net increase (decrease) | $ | 298 |  |  | $ | 170 |  |  | $ | 40 |  |  | $ | 31 |  |  | $ | 9 |  |  | $ | 10 |  |  | $ | 30 |  |  | $ | 8 |
Accumulated other comprehensive loss (income) |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax expense | $ | (2 | ) |  | — |  |  | 1 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of prior year service credit | 1 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of prior year actuarial losses | 10 |  |  | — |  |  | (4 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amount recognized in accumulated other comprehensive income | $ | 9 |  |  | $ | — |  |  | $ | (3 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
| Year Ended December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Regulatory assets, net (decrease) increase | $ | (212 | ) |  | $ | (70 | ) |  | $ | (49 | ) |  | $ | (37 | ) |  | $ | (11 | ) |  | $ | 9 |  |  | $ | (19 | ) |  | $ | (64 | )
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax expense | $ | — |  |  | $ | — |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Prior year service credit arising during the year | 1 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Amortization of prior year actuarial losses | (7 | ) |  | — |  |  | (7 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amount recognized in accumulated other comprehensive income | $ | (6 | ) |  | $ | — |  |  | $ | (4 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Piedmont's regulatory asset net increase was $34 million and $35 million for the two months ended December 31, 2016, and for the year ended October 31, 2016, respectively. Reconciliation of Funded Status to Net Amount Recognized
| Year Ended December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Change in Projected Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligation at prior measurement date | $ | 8,448 |  |  | $ | 2,029 |  |  | $ | 2,637 |  |  | $ | 1,211 |  |  | $ | 1,410 |  |  | $ | 479 |  |  | $ | 669 |  |  | $ | 313 |
Service cost | 174 |  |  | 56 |  |  | 49 |  |  | 28 |  |  | 21 |  |  | 5 |  |  | 10 |  |  | 7 |
Interest cost | 299 |  |  | 72 |  |  | 94 |  |  | 43 |  |  | 50 |  |  | 17 |  |  | 23 |  |  | 11 |
Actuarial gain | (485 | ) |  | (44 | ) |  | (204 | ) |  | (87 | ) |  | (114 | ) |  | (29 | ) |  | (29 | ) |  | (18 | )
Transfers | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (16 | )
Benefits paid | (567 | ) |  | (159 | ) |  | (143 | ) |  | (70 | ) |  | (72 | ) |  | (37 | ) |  | (55 | ) |  | (33 | )
Obligation at measurement date | $ | 7,869 |  |  | $ | 1,954 |  |  | $ | 2,433 |  |  | $ | 1,125 |  |  | $ | 1,295 |  |  | $ | 435 |  |  | $ | 618 |  |  | $ | 264 |
Accumulated Benefit Obligation at measurement date | $ | 7,818 |  |  | $ | 1,954 |  |  | $ | 2,404 |  |  | $ | 1,125 |  |  | $ | 1,265 |  |  | $ | 425 |  |  | $ | 614 |  |  | $ | 264 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Plan assets at prior measurement date | $ | 9,003 |  |  | $ | 2,372 |  |  | $ | 2,814 |  |  | $ | 1,366 |  |  | $ | 1,429 |  |  | $ | 458 |  |  | $ | 684 |  |  | $ | 368 |
Employer contributions | 141 |  |  | 46 |  |  | 45 |  |  | 25 |  |  | 20 |  |  | — |  |  | 8 |  |  | — |
Actual return on plan assets | (344 | ) |  | (91 | ) |  | (110 | ) |  | (53 | ) |  | (55 | ) |  | (16 | ) |  | (26 | ) |  | (14 | )
Benefits paid | (567 | ) |  | (159 | ) |  | (143 | ) |  | (70 | ) |  | (72 | ) |  | (37 | ) |  | (55 | ) |  | (33 | )
Transfers | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (16 | )
Plan assets at measurement date | $ | 8,233 |  |  | $ | 2,168 |  |  | $ | 2,606 |  |  | $ | 1,268 |  |  | $ | 1,322 |  |  | $ | 405 |  |  | $ | 611 |  |  | $ | 305 |
Funded status of plan | $ | 364 |  |  | $ | 214 |  |  | $ | 173 |  |  | $ | 143 |  |  | $ | 27 |  |  | $ | (30 | ) |  | $ | (7 | ) |  | $ | 41 |
| Year Ended December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Change in Projected Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligation at prior measurement date | $ | 8,131 |  |  | $ | 1,952 |  |  | $ | 2,512 |  |  | $ | 1,158 |  |  | $ | 1,323 |  |  | $ | 447 |  |  | $ | 658 |  |  | $ | 344 |
Service cost | 159 |  |  | 48 |  |  | 45 |  |  | 26 |  |  | 19 |  |  | 4 |  |  | 9 |  |  | 10 |
Interest cost | 328 |  |  | 79 |  |  | 100 |  |  | 47 |  |  | 53 |  |  | 18 |  |  | 26 |  |  | 14 |
Actuarial loss | 455 |  |  | 68 |  |  | 158 |  |  | 57 |  |  | 99 |  |  | 35 |  |  | 26 |  |  | 38 |
Transfers | — |  |  | 27 |  |  | (32 | ) |  | (2 | ) |  | (15 | ) |  | 12 |  |  | — |  |  | — |
Plan amendments | (61 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (61 | )
Benefits paid | (537 | ) |  | (145 | ) |  | (146 | ) |  | (75 | ) |  | (69 | ) |  | (37 | ) |  | (50 | ) |  | (5 | )
Benefits paid — settlements | (27 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (27 | )
Obligation at measurement date | $ | 8,448 |  |  | $ | 2,029 |  |  | $ | 2,637 |  |  | $ | 1,211 |  |  | $ | 1,410 |  |  | $ | 479 |  |  | $ | 669 |  |  | $ | 313 |
Accumulated Benefit Obligation at measurement date | $ | 8,369 |  |  | $ | 2,029 |  |  | $ | 2,601 |  |  | $ | 1,211 |  |  | $ | 1,375 |  |  | $ | 468 |  |  | $ | 652 |  |  | $ | 313 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Plan assets at prior measurement date | $ | 8,531 |  |  | $ | 2,225 |  |  | $ | 2,675 |  |  | $ | 1,290 |  |  | $ | 1,352 |  |  | $ | 428 |  |  | $ | 657 |  |  | $ | 346 |
Employer contributions | 19 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 4 |  |  | — |  |  | 11 |
Actual return on plan assets | 1,017 |  |  | 265 |  |  | 317 |  |  | 153 |  |  | 161 |  |  | 51 |  |  | 77 |  |  | 43 |
Benefits paid | (537 | ) |  | (145 | ) |  | (146 | ) |  | (75 | ) |  | (69 | ) |  | (37 | ) |  | (50 | ) |  | (5 | )
Benefits paid — settlements | (27 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (27 | )
Transfers | — |  |  | 27 |  |  | (32 | ) |  | (2 | ) |  | (15 | ) |  | 12 |  |  | — |  |  | — |
Plan assets at measurement date | $ | 9,003 |  |  | $ | 2,372 |  |  | $ | 2,814 |  |  | $ | 1,366 |  |  | $ | 1,429 |  |  | $ | 458 |  |  | $ | 684 |  |  | $ | 368 |
Funded status of plan | $ | 555 |  |  | $ | 343 |  |  | $ | 177 |  |  | $ | 155 |  |  | $ | 19 |  |  | $ | (21 | ) |  | $ | 15 |  |  | $ | 55 |
Amounts Recognized in the Consolidated Balance Sheets
| December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Prefunded pension(a) | $ | 433 |  |  | $ | 214 |  |  | $ | 242 |  |  | $ | 143 |  |  | $ | 96 |  |  | $ | 24 |  |  | $ | 39 |  |  | $ | 41 |
Noncurrent pension liability(b) | $ | 69 |  |  | $ | — |  |  | $ | 69 |  |  | $ | — |  |  | $ | 69 |  |  | $ | 54 |  |  | $ | 46 |  |  | $ | — |
Net asset (liability) recognized | $ | 364 |  |  | $ | 214 |  |  | $ | 173 |  |  | $ | 143 |  |  | $ | 27 |  |  | $ | (30 | ) |  | $ | (7 | ) |  | $ | 41 |
Regulatory assets | $ | 2,184 |  |  | $ | 576 |  |  | $ | 796 |  |  | $ | 372 |  |  | $ | 424 |  |  | $ | 100 |  |  | $ | 182 |  |  | $ | 81 |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | (43 | ) |  | $ | — |  |  | $ | (2 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Prior service credit | (4 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net actuarial loss | 126 |  |  | — |  |  | 5 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amounts recognized in accumulated other comprehensive loss | $ | 79 |  |  | $ | — |  |  | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Amounts to be recognized in net periodic pension costs in the next year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized net actuarial loss | $ | 97 |  |  | $ | 22 |  |  | $ | 37 |  |  | $ | 13 |  |  | $ | 24 |  |  | $ | 3 |  |  | $ | 5 |  |  | $ | 7 |
Unrecognized prior service credit | (32 | ) |  | (8 | ) |  | (3 | ) |  | (2 | ) |  | (1 | ) |  | — |  |  | (2 | ) |  | (9 | )
| December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Prefunded pension(a) | $ | 680 |  |  | $ | 343 |  |  | $ | 245 |  |  | $ | 155 |  |  | $ | 87 |  |  | $ | 8 |  |  | $ | 16 |  |  | $ | 55 |
Noncurrent pension liability(b) | $ | 125 |  |  | $ | — |  |  | $ | 68 |  |  | $ | — |  |  | $ | 68 |  |  | $ | 29 |  |  | $ | 1 |  |  | $ | — |
Net asset recognized | $ | 555 |  |  | $ | 343 |  |  | $ | 177 |  |  | $ | 155 |  |  | $ | 19 |  |  | $ | (21 | ) |  | $ | 15 |  |  | $ | 55 |
Regulatory assets | $ | 1,886 |  |  | $ | 406 |  |  | $ | 756 |  |  | $ | 341 |  |  | $ | 415 |  |  | $ | 90 |  |  | $ | 152 |  |  | $ | 73 |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | (41 | ) |  | $ | — |  |  | $ | (3 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Prior service credit | (5 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net actuarial loss | 116 |  |  | — |  |  | 9 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amounts recognized in accumulated other comprehensive loss | $ | 70 |  |  | $ | — |  |  | $ | 6 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Amounts to be recognized in net periodic pension costs in the next year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized net actuarial loss | $ | 132 |  |  | $ | 29 |  |  | $ | 44 |  |  | $ | 21 |  |  | $ | 23 |  |  | $ | 5 |  |  | $ | 7 |  |  | $ | 11 |
Unrecognized prior service credit | $ | (32 | ) |  | $ | (8 | ) |  | $ | (3 | ) |  | $ | (2 | ) |  | $ | (1 | ) |  | $ | — |  |  | $ | (2 | ) |  | $ | (9 | )
(a) | Included in Other within Other Noncurrent Assets on the Consolidated Balance Sheets.
(b) | Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets.
Information for Plans with Accumulated Benefit Obligation in Excess of Plan Assets
| December 31, 2018
|  |  | Duke |  | Duke |  | Duke |
| Duke |  | Progress |  | Energy |  | Energy |  | Energy |
(in millions) | Energy |  | Energy |  | Florida |  | Ohio |  | Indiana |
Projected benefit obligation | $ | 679 |  | $ | 679 |  | $ | 679 |  | $ | 123 |  | $ | 203 |
Accumulated benefit obligation | 651 |  | 651 |  | 651 |  | 115 |  | 199 |
Fair value of plan assets | 610 |  | 610 |  | 610 |  | 69 |  | 159 |
| December 31, 2017
|  |  | Duke |  | Duke |
| Duke |  | Progress |  | Energy |  | Energy |
(in millions) | Energy |  | Energy |  | Florida |  | Ohio |
Projected benefit obligation | $ | 1,386 |  | $ | 718 |  | $ | 718 |  | $ | 337 |
Accumulated benefit obligation | 1,326 |  | 683 |  | 683 |  | 326 |
Fair value of plan assets | 1,260 |  | 650 |  | 650 |  | 308 |
Assumptions Used for Pension Benefits Accounting The discount rate used to determine the current year pension obligation and following year’s pension expense is based on a bond selection-settlement portfolio approach. This approach develops a discount rate by selecting a portfolio of high quality corporate bonds that generate sufficient cash flow to provide for projected benefit payments of the plan. The selected bond portfolio is derived from a universe of non-callable corporate bonds rated Aa quality or higher. After the bond portfolio is selected, a single interest rate is determined that equates the present value of the plan’s projected benefit payments discounted at this rate with the market value of the bonds selected. The average remaining service period for participants in active plans and life expectancy of participants in inactive plans is 13 years for Duke Energy and Duke Energy Progress, 12 years for Duke Energy Carolinas, Progress Energy, and Duke Energy Florida, 14 years for Duke Energy Ohio and Duke Energy Indiana, and 10 years for Piedmont. The following tables present the assumptions or range of assumptions used for pension benefit accounting.
|  | December 31,
|  | 2018 |  | 2017 |  | 2016
Benefit Obligations |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  |  | 4.30% |  |  |  | 3.60% |  |  |  | 4.10%
Salary increase |  | 3.50 | % | – | 4.00% |  | 3.50 | % | – | 4.00% |  | 4.00 | % | – | 4.50%
Net Periodic Benefit Cost |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  |  | 3.60% |  |  |  | 4.10% |  |  |  |  | 4.40%
Salary increase |  | 3.50 | % | – | 4.00% |  | 4.00 | % | – | 4.50% |  | 4.00 | % | – | 4.40%
Expected long-term rate of return on plan assets |  |  |  |  | 6.50% |  | 6.50 | % | – | 6.75% |  | 6.50 | % | – | 6.75%
|  | Piedmont
|  | Two Months Ended |  | Year Ended
|  | December 31, 2016 |  | October 31, 2016
Benefit Obligations |  |  |  |
Discount rate |  | 4.10 | % |  | 3.80 | %
Salary increase |  | 4.50 | % |  | 4.05 | %
Net Periodic Benefit Cost |  |  |  |  |
Discount rate |  | 3.80 | % |  | 4.34 | %
Salary increase |  | 4.05 | % |  | 4.07 | %
Expected long-term rate of return on plan assets |  | 6.75 | % |  | 7.25 | %
Expected Benefit Payments
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Years ending December 31, |  |  |  |  |  |  |  |
2019 | $ | 662 |  | $ | 210 |  | $ | 179 |  | $ | 105 |  | $ | 73 |  | $ | 33 |  | $ | 47 |  | $ | 20 |
2020 | 651 |  | 177 |  | 171 |  | 90 |  | 80 |  | 37 |  | 51 |  | 24 |
2021 | 663 |  | 182 |  | 177 |  | 95 |  | 81 |  | 37 |  | 51 |  | 23 |
2022 | 662 |  | 189 |  | 179 |  | 94 |  | 84 |  | 37 |  | 49 |  | 22 |
2023 | 655 |  | 185 |  | 181 |  | 95 |  | 85 |  | 35 |  | 47 |  | 22 |
2024-2028 | 2,993 |  | 794 |  | 902 |  | 451 |  | 447 |  | 158 |  | 217 |  | 96 |
NON-QUALIFIED PENSION PLANS Components of Net Periodic Pension Costs
| Year Ended December 31, 2018
|  | Duke |  |  | Duke |  | Duke |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |
Service cost | $ | 2 |  | $ | 1 |  | $ | — |  | $ | — |  | $ | — |
Interest cost on projected benefit obligation | 12 |  | — |  | 4 |  | 1 |  | 2 |
Amortization of actuarial loss | 8 |  | — |  | 2 |  | 1 |  | 1 |
Amortization of prior service credit | (2 | ) | — |  | — |  | — |  | — |
Net periodic pension costs | $ | 20 |  | $ | 1 |  | $ | 6 |  | $ | 2 |  | $ | 3 |
| Year Ended December 31, 2017
|  | Duke |  |  | Duke |  | Duke |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |
Service cost | $ | 2 |  | $ | 1 |  | $ | — |  | $ | — |  | $ | — |
Interest cost on projected benefit obligation | 13 |  | 1 |  | 5 |  | 1 |  | 2 |
Amortization of actuarial loss | 8 |  | — |  | 2 |  | 1 |  | 1 |
Amortization of prior service credit | (2 | ) | — |  | — |  | — |  | — |
Net periodic pension costs | $ | 21 |  | $ | 2 |  | $ | 7 |  | $ | 2 |  | $ | 3 |
| Year Ended December 31, 2016
|  | Duke |  |  | Duke |  | Duke |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |
Service cost | $ | 2 |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Interest cost on projected benefit obligation | 14 |  | 1 |  | 5 |  | 1 |  | 2 |
Amortization of actuarial loss | 8 |  | 1 |  | 1 |  | 1 |  | 1 |
Amortization of prior service credit | (1 | ) | — |  | — |  | — |  | — |
Net periodic pension costs | $ | 23 |  | $ | 2 |  | $ | 6 |  | $ | 2 |  | $ | 3 |
| Piedmont
| Year Ended
(in millions) | October 31, 2016
Amortization of prior service cost | $ | — |
Settlement charge | 1 |
Net periodic pension costs | $ | 1 |
Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets and Liabilities
| Year Ended December 31, 2018
|  | Duke |  |  | Duke |  | Duke |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |
Regulatory assets, net (decrease) increase | $ | (16 | ) | $ | 1 |  | $ | (6 | ) | $ | (3 | ) | $ | (3 | )
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | 1 |  | $ | — |  | $ | 1 |  | $ | — |  | $ | — |
Actuarial gain arising during the year | (4 | ) | — |  | (3 | ) | — |  | — |
Net amount recognized in accumulated other comprehensive loss (income) | $ | (3 | ) | $ | — |  | $ | (2 | ) | $ | — |  | $ | — |
| Year Ended December 31, 2017
|  | Duke |  |  | Duke |  | Duke |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |
Regulatory assets, net increase (decrease) | $ | 5 |  | $ | (1 | ) | $ | 3 |  | $ | 1 |  | $ | 2 |
Accumulated other comprehensive (income) loss |  |  |  |  |
Prior service credit arising during the year | $ | (1 | ) | $ | — |  | $ | — |  | $ | — |  | $ | — |
Actuarial loss arising during the year | 2 |  | — |  | — |  | — |  | — |
Net amount recognized in accumulated other comprehensive loss (income) | $ | 1 |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Reconciliation of Funded Status to Net Amount Recognized
| Year Ended December 31, 2018
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Change in Projected Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligation at prior measurement date | $ | 331 |  | $ | 14 |  | $ | 116 |  | $ | 35 |  | $ | 47 |  | $ | 4 |  | $ | 3 |  | $ | 4 |
Service cost | 2 |  | 1 |  | — |  | — |  | — |  | — |  | — |  | — |
Interest cost | 12 |  | — |  | 4 |  | 1 |  | 2 |  | — |  | — |  | — |
Actuarial gain | (17 | ) | — |  | (6 | ) | (2 | ) | (3 | ) | (1 | ) | — |  | (1 | )
Benefits paid | (24 | ) | (1 | ) | (8 | ) | (3 | ) | (3 | ) | — |  | — |  | — |
Obligation at measurement date | $ | 304 |  | $ | 14 |  | $ | 106 |  | $ | 31 |  | $ | 43 |  | $ | 3 |  | $ | 3 |  | $ | 3 |
Accumulated Benefit Obligation at measurement date | $ | 304 |  | $ | 14 |  | $ | 106 |  | $ | 31 |  | $ | 43 |  | $ | 3 |  | $ | 3 |  | $ | 3 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Benefits paid | $ | (24 | ) | $ | (1 | ) | $ | (8 | ) | $ | (3 | ) | $ | (3 | ) | $ | — |  | $ | — |  | $ | — |
Employer contributions | 24 |  | 1 |  | 8 |  | 3 |  | 3 |  | — |  | — |  | — |
Plan assets at measurement date | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
| Year Ended December 31, 2017
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Change in Projected Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |
Obligation at prior measurement date | $ | 332 |  | $ | 14 |  | $ | 114 |  | $ | 33 |  | $ | 46 |  | $ | 4 |  | $ | 3 |  | $ | 4 |
Service cost | 2 |  | 1 |  | — |  | — |  | — |  | — |  | — |  | — |
Interest cost | 13 |  | 1 |  | 5 |  | 1 |  | 2 |  | — |  | — |  | — |
Actuarial loss (gain) | 15 |  | — |  | 5 |  | 4 |  | 2 |  | — |  | — |  | — |
Benefits paid | (31 | ) | (2 | ) | (8 | ) | (3 | ) | (3 | ) | — |  | — |  | — |
Obligation at measurement date | $ | 331 |  | $ | 14 |  | $ | 116 |  | $ | 35 |  | $ | 47 |  | $ | 4 |  | $ | 3 |  | $ | 4 |
Accumulated Benefit Obligation at measurement date | $ | 331 |  | $ | 14 |  | $ | 116 |  | $ | 35 |  | $ | 47 |  | $ | 4 |  | $ | 3 |  | $ | 4 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Benefits paid | $ | (31 | ) | $ | (2 | ) | $ | (8 | ) | $ | (3 | ) | $ | (3 | ) | $ | — |  | $ | — |  | $ | — |
Employer contributions | 31 |  | 2 |  | 8 |  | 3 |  | 3 |  | — |  | — |  | — |
Plan assets at measurement date | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Amounts Recognized in the Consolidated Balance Sheets
| December 31, 2018
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Current pension liability(a) | $ | 21 |  | $ | 2 |  | $ | 8 |  | $ | 3 |  | $ | 3 |  | $ | — |  | $ | — |  | $ | — |
Noncurrent pension liability(b) | 283 |  | 12 |  | 98 |  | 28 |  | 40 |  | 3 |  | 3 |  | 3 |
Total accrued pension liability | $ | 304 |  | $ | 14 |  | $ | 106 |  | $ | 31 |  | $ | 43 |  | $ | 3 |  | $ | 3 |  | $ | 3 |
Regulatory assets | $ | 62 |  | $ | 5 |  | $ | 15 |  | $ | 5 |  | $ | 10 |  | $ | 1 |  | $ | — |  | $ | 1 |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | (3 | ) | $ | — |  | $ | (2 | ) | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Prior service credit | (1 | ) | — |  | — |  | — |  | — |  | — |  | — |  | — |
Net actuarial loss | 8 |  | — |  | 6 |  | — |  | — |  | — |  | — |  | — |
Net amounts recognized in accumulated other comprehensive loss | $ | 4 |  | $ | — |  | $ | 4 |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Amounts to be recognized in net periodic pension expense in the next year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized net actuarial loss | $ | 6 |  | $ | — |  | $ | 2 |  | $ | 1 |  | $ | 1 |  | $ | — |  | $ | — |  | $ | — |
Unrecognized prior service credit | (2 | ) | — |  | — |  | — |  | — |  | — |  | — |  | — |
| December 31, 2017
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Current pension liability(a) | $ | 23 |  | $ | 2 |  | $ | 8 |  | $ | 3 |  | $ | 3 |  | $ | — |  | $ | — |  | $ | — |
Noncurrent pension liability(b) | 308 |  | 12 |  | 108 |  | 32 |  | 44 |  | 4 |  | 3 |  | 4 |
Total accrued pension liability | $ | 331 |  | $ | 14 |  | $ | 116 |  | $ | 35 |  | $ | 47 |  | $ | 4 |  | $ | 3 |  | $ | 4 |
Regulatory assets | $ | 78 |  | $ | 4 |  | $ | 21 |  | $ | 8 |  | $ | 13 |  | $ | 1 |  | $ | — |  | $ | 1 |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | (4 | ) | $ | — |  | $ | (3 | ) | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Prior service credit | (1 | ) | — |  | — |  | — |  | — |  | — |  | — |  | — |
Net actuarial loss | 12 |  | — |  | 9 |  | — |  | — |  | — |  | — |  | — |
Net amounts recognized in accumulated other comprehensive loss | $ | 7 |  | $ | — |  | $ | 6 |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Amounts to be recognized in net periodic pension expense in the next year |  |  |  |  |  |  |  |
Unrecognized net actuarial loss | $ | 8 |  | $ | — |  | $ | 2 |  | $ | 1 |  | $ | 1 |  | $ | — |  | $ | — |  | $ | — |
Unrecognized prior service credit | $ | (2 | ) | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
(a) Included in Other within Current Liabilities on the Consolidated Balance Sheets. (b) Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets. Information for Plans with Accumulated Benefit Obligation in Excess of Plan Assets
| December 31, 2018
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Projected benefit obligation | $ | 304 |  | $ | 14 |  | $ | 106 |  | $ | 31 |  | $ | 43 |  | $ | 3 |  | $ | 3 |  | $ | 3 |
Accumulated benefit obligation | 304 |  | 14 |  | 106 |  | 31 |  | 43 |  | 3 |  | 3 |  | 3 |
| December 31, 2017
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Projected benefit obligation | $ | 331 |  | $ | 14 |  | $ | 116 |  | $ | 35 |  | $ | 47 |  | $ | 4 |  | $ | 3 |  | $ | 4 |
Accumulated benefit obligation | 331 |  | 14 |  | 116 |  | 35 |  | 47 |  | 4 |  | 3 |  | 4 |
Assumptions Used for Pension Benefits Accounting The discount rate used to determine the current year pension obligation and following year’s pension expense is based on a bond selection-settlement portfolio approach. This approach develops a discount rate by selecting a portfolio of high quality corporate bonds that generate sufficient cash flow to provide for projected benefit payments of the plan. The selected bond portfolio is derived from a universe of non-callable corporate bonds rated Aa quality or higher. After the bond portfolio is selected, a single interest rate is determined that equates the present value of the plan’s projected benefit payments discounted at this rate with the market value of the bonds selected. The average remaining service period of active covered employees is 10 years for Duke Energy, 13 years for Progress Energy, 11 years for Duke Energy Progress, 15 years for Duke Energy Florida, eight years for Duke Energy Carolinas, Duke Energy Ohio, Duke Energy Indiana and Piedmont. The following tables present the assumptions used for pension benefit accounting.
|  | December 31,
|  | 2018 |  | 2017 |  | 2016 |
Benefit Obligations |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  |  |  | 4.30 | % |  |  |  | 3.60 | % |  | 4.10 | %
Salary increase |  | 3.50 | % | – | 4.00 | % |  | 3.50 | % | – | 4.00 | % |  | 4.40 | %
Net Periodic Benefit Cost |  |  |  |  |  |  |  |  |  |  |  |  |
Discount rate |  |  |  | 3.60 | % |  |  |  | 4.10 | % |  | 4.40 | %
Salary increase |  | 3.50 | % | – | 4.00 | % |  |  |  | 4.40 | % |  | 4.40 | %
|  | Piedmont
|  | Two Months Ended |  | Year Ended
|  | December 31, 2016 |  | October 31, 2016
Benefit Obligations |  |  |  |
Discount rate |  | 4.10 | % |  | 3.80 | %
Net Periodic Benefit Cost |  |  |  |  |
Discount rate |  | 3.80 | % |  | 3.85 | %
Expected Benefit Payments
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Years ending December 31, |  |  |  |  |  |  |  |
2019 | $ | 22 |  | $ | 2 |  | $ | 8 |  | $ | 3 |  | $ | 3 |  | $ | — |  | $ | — |  | $ | — |
2020 | 21 |  | 1 |  | 8 |  | 2 |  | 3 |  | — |  | — |  | — |
2021 | 23 |  | 1 |  | 8 |  | 2 |  | 3 |  | — |  | — |  | — |
2022 | 25 |  | 1 |  | 8 |  | 2 |  | 3 |  | — |  | — |  | — |
2023 | 25 |  | 3 |  | 7 |  | 2 |  | 3 |  | — |  | — |  | — |
2024-2028 | 125 |  | 10 |  | 37 |  | 11 |  | 15 |  | 1 |  | 1 |  | 2 |
OTHER POST-RETIREMENT BENEFIT PLANS Duke Energy provides, and the Subsidiary Registrants participate in, some health care and life insurance benefits for retired employees on a contributory and non-contributory basis. Employees are eligible for these benefits if they have met age and service requirements at retirement, as defined in the plans. The health care benefits include medical, dental and prescription drug coverage and are subject to certain limitations, such as deductibles and copayments. Duke Energy did not make any pre-funding contributions to its other post-retirement benefit plans during the years ended December 31, 2018, 2017 or 2016. Components of Net Periodic Other Post-Retirement Benefit Costs
| Year Ended December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Service cost | $ | 6 |  |  | $ | 1 |  |  | $ | 1 |  |  | $ | — |  |  | $ | 1 |  |  | $ | 1 |  |  | $ | 1 |  |  | $ | 1 |
Interest cost on accumulated post-retirement benefit obligation | 28 |  |  | 7 |  |  | 12 |  |  | 6 |  |  | 6 |  |  | 1 |  |  | 3 |  |  | 1 |
Expected return on plan assets | (13 | ) |  | (8 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (2 | )
Amortization of actuarial loss | 6 |  |  | 3 |  |  | 1 |  |  | 1 |  |  | — |  |  | — |  |  | 4 |  |  | — |
Amortization of prior service credit | (19 | ) |  | (5 | ) |  | (8 | ) |  | (1 | ) |  | (7 | ) |  | (1 | ) |  | (1 | ) |  | (2 | )
Net periodic post-retirement benefit costs (a)(b) | $ | 8 |  |  | $ | (2 | ) |  | $ | 6 |  |  | $ | 6 |  |  | $ | — |  |  | $ | 1 |  |  | $ | 7 |  |  | $ | (2 | )
| Year Ended December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Service cost | $ | 4 |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 1 |
Interest cost on accumulated post-retirement benefit obligation | 34 |  |  | 8 |  |  | 13 |  |  | 7 |  |  | 6 |  |  | 1 |  |  | 3 |  |  | 1 |
Expected return on plan assets | (14 | ) |  | (8 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | (1 | ) |  | (2 | )
Amortization of actuarial loss (gain) | 10 |  |  | (2 | ) |  | 21 |  |  | 12 |  |  | 9 |  |  | (2 | ) |  | (1 | ) |  | 1 |
Amortization of prior service credit | (115 | ) |  | (10 | ) |  | (84 | ) |  | (54 | ) |  | (30 | ) |  | — |  |  | (1 | ) |  | — |
Curtailment credit (c) | (30 | ) |  | (4 | ) |  | (16 | ) |  | — |  |  | (16 | ) |  | (2 | ) |  | (2 | ) |  | — |
Net periodic post-retirement benefit costs(a)(b) | $ | (111 | ) |  | $ | (15 | ) |  | $ | (66 | ) |  | $ | (35 | ) |  | $ | (31 | ) |  | $ | (3 | ) |  | $ | (2 | ) |  | $ | 1 |
| Year Ended December 31, 2016
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |
Service cost | $ | 3 |  |  | $ | 1 |  |  | $ | 1 |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |
Interest cost on accumulated post-retirement benefit obligation | 35 |  |  | 8 |  |  | 15 |  |  | 8 |  |  | 7 |  |  | 1 |  |  | 4 |
Expected return on plan assets | (12 | ) |  | (8 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | (1 | )
Amortization of actuarial loss (gain) | 6 |  |  | (3 | ) |  | 22 |  |  | 13 |  |  | 9 |  |  | (2 | ) |  | (1 | )
Amortization of prior service credit | (141 | ) |  | (14 | ) |  | (103 | ) |  | (68 | ) |  | (35 | ) |  | — |  |  | (1 | )
Net periodic post-retirement benefit costs(a)(b) | $ | (109 | ) |  | $ | (16 | ) |  | $ | (65 | ) |  | $ | (47 | ) |  | $ | (18 | ) |  | $ | (1 | ) |  | $ | 1 |
(a) | Duke Energy amounts exclude $7 million, $7 million and $8 million for the years ended December 2018, 2017 and 2016, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006.
(b) | Duke Energy Ohio amounts exclude $2 million, $2 million and $2 million for the years ended December 2018, 2017 and 2016, respectively, of regulatory asset amortization resulting from purchase accounting adjustments associated with Duke Energy's merger with Cinergy in April 2006.
(c) | Curtailment credit resulted from a reduction in average future service of plan participants due to a plan amendment.
| Piedmont
| Year Ended
(in millions) | October 31, 2016
Service cost | $ | 1 |
Interest cost on projected benefit obligation | 1 |
Expected return on plan assets | (2 | )
Amortization of actuarial loss | 1 |
Net periodic pension costs | $ | 1 |
Amounts Recognized in Accumulated Other Comprehensive Income and Regulatory Assets and Liabilities
| Year Ended December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Regulatory assets, net increase (decrease) | $ | 137 |  |  | $ | — |  |  | $ | 133 |  |  | $ | 84 |  |  | $ | 49 |  |  | $ | — |  |  | $ | (5 | ) |  | $ | 4 |
Regulatory liabilities, net increase (decrease) | $ | 154 |  |  | $ | (6 | ) |  | $ | 149 |  |  | $ | 93 |  |  | $ | 56 |  |  | $ | 2 |  |  | $ | 3 |  |  | $ | — |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | (1 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Amortization of prior year actuarial gain | 1 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amount recognized in accumulated other comprehensive income | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
| Year Ended December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Regulatory assets, net increase (decrease) | $ | 71 |  |  | $ | — |  |  | $ | 81 |  |  | $ | 42 |  |  | $ | 39 |  |  | $ | — |  |  | $ | (5 | ) |  | $ | (11 | )
Regulatory liabilities, net increase (decrease) | $ | (27 | ) |  | $ | (2 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | (3 | ) |  | $ | (7 | ) |  | $ | — |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit | $ | (1 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Amortization of prior year prior service credit | 3 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amount recognized in accumulated other comprehensive income | $ | 2 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Piedmont's regulatory assets net decreased $1 million for the two months ended December 31, 2016, and increased $2 million for the year ended October 31, 2016. Reconciliation of Funded Status to Accrued Other Post-Retirement Benefit Costs
| Year Ended December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Change in Projected Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accumulated post-retirement benefit obligation at prior measurement date | $ | 813 |  |  | $ | 189 |  |  | $ | 342 |  |  | $ | 184 |  |  | $ | 156 |  |  | $ | 30 |  |  | $ | 78 |  |  | $ | 32 |
Service cost | 6 |  |  | 1 |  |  | 1 |  |  | — |  |  | 1 |  |  | 1 |  |  | 1 |  |  | 1 |
Interest cost | 28 |  |  | 7 |  |  | 12 |  |  | 6 |  |  | 6 |  |  | 1 |  |  | 3 |  |  | 1 |
Plan participants' contributions | 18 |  |  | 3 |  |  | 6 |  |  | 4 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | — |
Actuarial gains | (51 | ) |  | (8 | ) |  | (23 | ) |  | (9 | ) |  | (13 | ) |  | (2 | ) |  | (5 | ) |  | (1 | )
Transfers | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1 | )
Benefits paid | (86 | ) |  | (18 | ) |  | (35 | ) |  | (19 | ) |  | (16 | ) |  | (2 | ) |  | (12 | ) |  | (2 | )
Accumulated post-retirement benefit obligation at measurement date | $ | 728 |  |  | $ | 174 |  |  | $ | 303 |  |  | $ | 166 |  |  | $ | 137 |  |  | $ | 29 |  |  | $ | 67 |  |  | $ | 30 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Plan assets at prior measurement date | $ | 225 |  |  | $ | 133 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 7 |  |  | $ | 11 |  |  | $ | 31 |
Actual return on plan assets | (8 | ) |  | (5 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | (1 | )
Benefits paid | (86 | ) |  | (18 | ) |  | (35 | ) |  | (19 | ) |  | (16 | ) |  | (2 | ) |  | (12 | ) |  | (2 | )
Employer contributions | 46 |  |  | 2 |  |  | 29 |  |  | 15 |  |  | 13 |  |  | 2 |  |  | 4 |  |  | 1 |
Plan participants' contributions | 18 |  |  | 3 |  |  | 6 |  |  | 4 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | — |
Plan assets at measurement date | $ | 195 |  |  | $ | 115 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 8 |  |  | $ | 5 |  |  | $ | 29 |
Funded status of plan | $ | (533 | ) |  | $ | (59 | ) |  | $ | (303 | ) |  | $ | (166 | ) |  | $ | (137 | ) |  | $ | (21 | ) |  | $ | (62 | ) |  | $ | (1 | )
| Year Ended December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Change in Projected Benefit Obligation |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Accumulated post-retirement benefit obligation at prior measurement date | $ | 868 |  |  | $ | 201 |  |  | $ | 357 |  |  | $ | 191 |  |  | $ | 164 |  |  | $ | 32 |  |  | $ | 83 |  |  | $ | 39 |
Service cost | 4 |  |  | 1 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | 1 |
Interest cost | 34 |  |  | 8 |  |  | 13 |  |  | 7 |  |  | 6 |  |  | 1 |  |  | 3 |  |  | 1 |
Plan participants' contributions | 17 |  |  | 3 |  |  | 6 |  |  | 3 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | — |
Actuarial losses (gains) | 4 |  |  | (3 | ) |  | 4 |  |  | 1 |  |  | 3 |  |  | — |  |  | 3 |  |  | 1 |
Transfers | — |  |  | 2 |  |  | (1 | ) |  | — |  |  | (1 | ) |  | 1 |  |  | — |  |  | — |
Plan amendments | (28 | ) |  | (5 | ) |  | (3 | ) |  | (1 | ) |  | (2 | ) |  | (2 | ) |  | (2 | ) |  | (9 | )
Benefits paid | (86 | ) |  | (18 | ) |  | (34 | ) |  | (17 | ) |  | (17 | ) |  | (3 | ) |  | (11 | ) |  | (1 | )
Accumulated post-retirement benefit obligation at measurement date | $ | 813 |  |  | $ | 189 |  |  | $ | 342 |  |  | $ | 184 |  |  | $ | 156 |  |  | $ | 30 |  |  | $ | 78 |  |  | $ | 32 |
Change in Fair Value of Plan Assets |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Plan assets at prior measurement date | $ | 244 |  |  | $ | 137 |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | 7 |  |  | $ | 22 |  |  | $ | 29 |
Actual return on plan assets | 25 |  |  | 15 |  |  | 1 |  |  | — |  |  | — |  |  | 2 |  |  | 1 |  |  | 3 |
Benefits paid | (86 | ) |  | (18 | ) |  | (34 | ) |  | (17 | ) |  | (17 | ) |  | (3 | ) |  | (11 | ) |  | (1 | )
Employer contributions (reimbursements) | 25 |  |  | (4 | ) |  | 26 |  |  | 14 |  |  | 14 |  |  | — |  |  | (3 | ) |  | — |
Plan participants' contributions | 17 |  |  | 3 |  |  | 6 |  |  | 3 |  |  | 3 |  |  | 1 |  |  | 2 |  |  | — |
Plan assets at measurement date | $ | 225 |  |  | $ | 133 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 7 |  |  | $ | 11 |  |  | $ | 31 |
Funded status of plan | $ | (588 | ) |  | $ | (56 | ) |  | $ | (342 | ) |  | $ | (184 | ) |  | $ | (156 | ) |  | $ | (23 | ) |  | $ | (67 | ) |  | $ | (1 | )
Amounts Recognized in the Consolidated Balance Sheets
| December 31, 2018
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Current post-retirement liability(a) | $ | 8 |  |  | $ | — |  |  | $ | 5 |  |  | $ | 3 |  |  | $ | 2 |  |  | $ | 2 |  |  | $ | — |  |  | $ | — |
Noncurrent post-retirement liability(b) | 525 |  |  | 59 |  |  | 298 |  |  | 163 |  |  | 135 |  |  | 19 |  |  | 62 |  |  | 1 |
Total accrued post-retirement liability | $ | 533 |  |  | $ | 59 |  |  | $ | 303 |  |  | $ | 166 |  |  | $ | 137 |  |  | $ | 21 |  |  | $ | 62 |  |  | $ | 1 |
Regulatory assets | $ | 262 |  |  | $ | — |  |  | $ | 262 |  |  | $ | 164 |  |  | $ | 98 |  |  | $ | — |  |  | $ | 41 |  |  | $ | — |
Regulatory liabilities | $ | 301 |  |  | $ | 38 |  |  | $ | 149 |  |  | $ | 93 |  |  | $ | 56 |  |  | $ | 18 |  |  | $ | 67 |  |  | $ | — |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax expense | $ | 3 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Prior service credit | (2 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net actuarial gain | (9 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amounts recognized in accumulated other comprehensive income | $ | (8 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Amounts to be recognized in net periodic pension expense in the next year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized net actuarial loss | $ | 4 |  |  | $ | 2 |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Unrecognized prior service credit | (19 | ) |  | (5 | ) |  | (7 | ) |  | (1 | ) |  | (6 | ) |  | (1 | ) |  | (1 | ) |  | (2 | )
| December 31, 2017
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont |
Current post-retirement liability(a) | $ | 36 |  |  | $ | — |  |  | $ | 29 |  |  | $ | 15 |  |  | $ | 14 |  |  | $ | 2 |  |  | $ | — |  |  | $ | — |
Noncurrent post-retirement liability(b) | 552 |  |  | 56 |  |  | 313 |  |  | 169 |  |  | 142 |  |  | 21 |  |  | 67 |  |  | 1 |
Total accrued post-retirement liability | $ | 588 |  |  | $ | 56 |  |  | $ | 342 |  |  | $ | 184 |  |  | $ | 156 |  |  | $ | 23 |  |  | $ | 67 |  |  | $ | 1 |
Regulatory assets | $ | 125 |  |  | $ | — |  |  | $ | 129 |  |  | $ | 80 |  |  | $ | 49 |  |  | $ | — |  |  | $ | 46 |  |  | $ | (4 | )
Regulatory liabilities | $ | 147 |  |  | $ | 44 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 16 |  |  | $ | 64 |  |  | $ | — |
Accumulated other comprehensive (income) loss |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax expense | $ | 4 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Prior service credit | (2 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net actuarial gain | (10 | ) |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Net amounts recognized in accumulated other comprehensive income | $ | (8 | ) |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Amounts to be recognized in net periodic pension expense in the next year |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unrecognized net actuarial loss (gain) | $ | 5 |  |  | $ | 3 |  |  | $ | 1 |  |  | $ | — |  |  | $ | 1 |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Unrecognized prior service credit | (19 | ) |  | (5 | ) |  | (7 | ) |  | (1 | ) |  | (6 | ) |  | (1 | ) |  | (1 | ) |  | (2 | )
(a) | Included in Other within Current Liabilities on the Consolidated Balance Sheets.
(b) | Included in Accrued pension and other post-retirement benefit costs on the Consolidated Balance Sheets.
Assumptions Used for Other Post-Retirement Benefits Accounting The discount rate used to determine the current year other post-retirement benefits obligation and following year’s other post-retirement benefits expense is based on a bond selection-settlement portfolio approach. This approach develops a discount rate by selecting a portfolio of high quality corporate bonds that generate sufficient cash flow to provide for projected benefit payments of the plan. The selected bond portfolio is derived from a universe of non-callable corporate bonds rated Aa quality or higher. After the bond portfolio is selected, a single interest rate is determined that equates the present value of the plan’s projected benefit payments discounted at this rate with the market value of the bonds selected. The average remaining service period of active covered employees is nine years for Duke Energy, eight years for Duke Energy Carolinas, seven years for Duke Energy Florida, Duke Energy Ohio, and Piedmont, and six years for Progress Energy, Duke Energy Progress, and Duke Energy Indiana. The following tables present the assumptions used for other post-retirement benefits accounting.
|  | December 31,
|  | 2018 |  |  | 2017 |  |  | 2016 |
Benefit Obligations |  |  |  |  |  |  |  |
Discount rate |  | 4.30 | % |  | 3.60 | % |  | 4.10 | %
Net Periodic Benefit Cost |  |  |  |  |  |  |  |
Discount rate |  | 3.60 | % |  | 4.10 | % |  | 4.40 | %
Expected long-term rate of return on plan assets |  | 6.50 | % |  | 6.50 | % |  | 6.50 | %
Assumed tax rate |  | 35 | % |  | 35 | % |  | 35 | %
|  | Piedmont
|  | Two Months Ended |  | Year Ended
|  | December 31, 2016 |  | October 31, 2016
Benefit Obligations |  |  |  |
Discount rate |  | 4.10 | % |  | 3.80 | %
Net Periodic Benefit Cost |  |  |  |  |
Discount rate |  | 3.80 | % |  | 4.38 | %
Expected long-term rate of return on plan assets |  | 6.75 | % |  | 7.25 | %
Assumed Health Care Cost Trend Rate
| December 31,
| 2018 |  |  | 2017 |
Health care cost trend rate assumed for next year | 6.50 | % |  | 7.00 | %
Rate to which the cost trend is assumed to decline (the ultimate trend rate) | 4.75 | % |  | 4.75 | %
Year that rate reaches ultimate trend | 2024 |  |  | 2024 |
Sensitivity to Changes in Assumed Health Care Cost Trend Rates
| Year Ended December 31, 2018
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
1-Percentage Point Increase |  |  |  |  |  |  |  |  |
Effect on total service and interest costs | $ | 1 |  | $ | — |  | $ | 1 |  | $ | 1 |  | $ | — |  | $ | — |  | $ | — |  | $ | — |
Effect on post-retirement benefit obligation | 22 |  | 5 |  | 9 |  | 5 |  | 4 |  | 1 |  | 2 |  | 1 |
1-Percentage Point Decrease |  |  |  |  |  |  |  |
Effect on total service and interest costs | (1 | ) | — |  | (1 | ) | (1 | ) | — |  | — |  | — |  | — |
Effect on post-retirement benefit obligation | (20 | ) | (5 | ) | (8 | ) | (5 | ) | (4 | ) | (1 | ) | (2 | ) | (1 | )
Expected Benefit Payments
|  | Duke |  |  | Duke |  | Duke |  | Duke |  | Duke |  |
| Duke |  | Energy |  | Progress |  | Energy |  | Energy |  | Energy |  | Energy |  |
(in millions) | Energy |  | Carolinas |  | Energy |  | Progress |  | Florida |  | Ohio |  | Indiana |  | Piedmont |
Years ending December 31, |  |  |  |  |  |  |  |  |
2019 | $ | 81 |  | $ | 19 |  | $ | 30 |  | $ | 16 |  | $ | 14 |  | $ | 3 |  | $ | 9 |  | $ | 2 |
2020 | 75 |  | 18 |  | 29 |  | 15 |  | 13 |  | 3 |  | 8 |  | 2 |
2021 | 71 |  | 18 |  | 28 |  | 15 |  | 13 |  | 3 |  | 7 |  | 2 |
2022 | 68 |  | 17 |  | 27 |  | 14 |  | 12 |  | 3 |  | 7 |  | 3 |
2023 | 64 |  | 16 |  | 26 |  | 14 |  | 12 |  | 3 |  | 6 |  | 3 |
2024-2028 | 266 |  | 64 |  | 109 |  | 59 |  | 50 |  | 11 |  | 26 |  | 12 |
PLAN ASSETS Description and Allocations Duke Energy Master Retirement Trust Assets for both the qualified pension and other post-retirement benefits are maintained in the Duke Energy Master Retirement Trust. Qualified pension and other post-retirement assets related to Piedmont were transferred into the Duke Energy Master Retirement Trust during 2017. Approximately 98 percent of the Duke Energy Master Retirement Trust assets were allocated to qualified pension plans and approximately 2 percent were allocated to other post-retirement plans (comprised of 401(h) accounts), as of December 31, 2018, and 2017. The investment objective of the Duke Energy Master Retirement Trust is to invest in a diverse portfolio of assets that is expected to generate positive surplus return over time (i.e. asset growth greater than liability growth) subject to a prudent level of portfolio risk, for the purpose of enhancing the security of benefits for plan participants. As of December 31, 2018, Duke Energy assumes pension and other post-retirement plan assets will generate a long-term rate of return of 6.85 percent. The expected long-term rate of return was developed using a weighted average calculation of expected returns based primarily on future expected returns across asset classes considering the use of active asset managers, where applicable. The asset allocation targets were set after considering the investment objective and the risk profile. Equity securities are held for their higher expected returns. Debt securities are primarily held to hedge the qualified pension plan liability. Real assets, return seeking fixed income, hedge funds and other global securities are held for diversification. Investments within asset classes are diversified to achieve broad market participation and reduce the impact of individual managers or investments. Effective January 1, 2019, the target asset allocation for the Duke Energy Retirement Master Trust is 58 percent liability hedging assets and 42 percent return-seeking assets. Duke Energy periodically reviews its asset allocation targets, and over time, as the funded status of the benefit plans increase, the level of asset risk relative to plan liabilities may be reduced to better manage Duke Energy's benefit plan liabilities and reduce funded status volatility. The Duke Energy Master Retirement Trust is authorized to engage in the lending of certain plan assets. Securities lending is an investment management enhancement that utilizes certain existing securities of the Duke Energy Master Retirement Trust to earn additional income. Securities lending involves the loaning of securities to approved parties. In return for the loaned securities, the Duke Energy Master Retirement Trust receives collateral in the form of cash and securities as a safeguard against possible default of any borrower on the return of the loan under terms that permit the Duke Energy Master Retirement Trust to sell the securities. The Duke Energy Master Retirement Trust mitigates credit risk associated with securities lending arrangements by monitoring the fair value of the securities loaned, with additional collateral obtained or refunded as necessary. The fair value of securities on loan was approximately $154 million and $195 million at December 31, 2018, and 2017, respectively. Cash and securities obtained as collateral exceeded the fair value of the securities loaned at December 31, 2018, and 2017, respectively. Securities lending income earned by the Duke Energy Master Retirement Trust was immaterial for the years ended December 31, 2018, 2017 and 2016, respectively. Qualified pension and other post-retirement benefits for the Subsidiary Registrants are derived from the Duke Energy Master Retirement Trust, as such, each are allocated their proportionate share of the assets discussed below. The following table includes the target asset allocations by asset class at December 31, 2018, and the actual asset allocations for the Duke Energy Master Retirement Trust.
|  |  | Actual Allocation at
| Target |  |  | December 31,
| Allocation |  |  | 2018 |  |  | 2017 |
U.S. equity securities | 10 | % |  | 11 | % |  | 11 | %
Non-U.S. equity securities | 8 | % |  | 8 | % |  | 8 | %
Global equity securities | 10 | % |  | 10 | % |  | 10 | %
Global private equity securities | 3 | % |  | 2 | % |  | 2 | %
Debt securities | 63 | % |  | 63 | % |  | 63 | %
Hedge funds | 2 | % |  | 2 | % |  | 2 | %
Real estate and cash | 2 | % |  | 2 | % |  | 2 | %
Other global securities | 2 | % |  | 2 | % |  | 2 | %
Total | 100 | % |  | 100 | % |  | 100 | %
Other post-retirement assets Duke Energy's other post-retirement assets are comprised of VEBA trusts and 401(h) accounts held within the Duke Energy Master Retirement Trust. Duke Energy's investment objective is to achieve sufficient returns, subject to a prudent level of portfolio risk, for the purpose of promoting the security of plan benefits for participants. The following table presents target and actual asset allocations for the VEBA trusts at December 31, 2018.
|  |  | Actual Allocation at
| Target |  |  | December 31,
| Allocation |  |  | 2018 |  |  | 2017 |
U.S. equity securities | 32 | % |  | 43 | % |  | 41 | %
Non-U.S. equity securities | 6 | % |  | 8 | % |  | 8 | %
Real estate | 2 | % |  | 2 | % |  | 2 | %
Debt securities | 45 | % |  | 40 | % |  | 36 | %
Cash | 15 | % |  | 7 | % |  | 13 | %
Total | 100 | % |  | 100 | % |  | 100 | %
Fair Value Measurements Duke Energy classifies recurring and non-recurring fair value measurements based on the fair value hierarchy as discussed in Note 16. Valuation methods of the primary fair value measurements disclosed below are as follows: Investments in equity securities Investments in equity securities are typically valued at the closing price in the principal active market as of the last business day of the reporting period. Principal active markets for equity prices include published exchanges such as NASDAQ and NYSE. Foreign equity prices are translated from their trading currency using the currency exchange rate in effect at the close of the principal active market. Prices have not been adjusted to reflect after-hours market activity. The majority of investments in equity securities are valued using Level 1 measurements. When the price of an institutional commingled fund is unpublished, it is not categorized in the fair value hierarchy, even though the funds are readily available at the fair value. Investments in corporate debt securities and U.S. government securities Most debt investments are valued based on a calculation using interest rate curves and credit spreads applied to the terms of the debt instrument (maturity and coupon interest rate) and consider the counterparty credit rating. Most debt valuations are Level 2 measurements. If the market for a particular fixed-income security is relatively inactive or illiquid, the measurement is Level 3. U.S. Treasury debt is typically Level 2. Investments in short-term investment funds Investments in short-term investment funds are valued at the net asset value of units held at year end and are readily redeemable at the measurement date. Investments in short-term investment funds with published prices are valued as Level 1. Investments in short-term investment funds with unpublished prices are valued as Level 2. Investments in real estate limited partnerships Investments in real estate limited partnerships are valued by the trustee at each valuation date (monthly). As part of the trustee’s valuation process, properties are externally appraised generally on an annual basis, conducted by reputable, independent appraisal firms, and signed by appraisers that are members of the Appraisal Institute, with the professional designation MAI. Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. There are three valuation techniques that can be used to value investments in real estate assets: the market, income or cost approach. The appropriateness of each valuation technique depends on the type of asset or business being valued. In addition, the trustee may cause additional appraisals to be performed as warranted by specific asset or market conditions. Property valuations and the salient valuation-sensitive assumptions of each direct investment property are reviewed by the trustee quarterly and values are adjusted if there has been a significant change in circumstances related to the investment property since the last valuation. Value adjustments for interim capital expenditures are only recognized to the extent that the valuation process acknowledges a corresponding increase in fair value. An independent firm is hired to review and approve quarterly direct real estate valuations. Key inputs and assumptions used to determine fair value includes among others, rental revenue and expense amounts and related revenue and expense growth rates, terminal capitalization rates and discount rates. Development investments are valued using cost incurred to date as a primary input until substantive progress is achieved in terms of mitigating construction and leasing risk at which point a discounted cash flow approach is more heavily weighted. Key inputs and assumptions in addition to those noted above used to determine the fair value of development investments include construction costs and the status of construction completion and leasing. Investments in real estate limited partnerships are valued at net asset value of units held at year end and are not readily redeemable at the measurement date. Investments in real estate limited partnerships are not categorized within the fair value hierarchy. Duke Energy Master Retirement Trust The following tables provide the fair value measurement amounts for the Duke Energy Master Retirement Trust qualified pension and other post-retirement assets.
| December 31, 2018
| Total Fair |  |  |  |  |  |  |  |  | Not |
(in millions) | Value |  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Categorized(b) |
Equity securities | $ | 2,373 |  |  | $ | 1,751 |  |  | $ | — |  |  | $ | — |  |  | $ | 622 |
Corporate debt securities | 4,054 |  |  | — |  |  | 4,054 |  |  | — |  |  | — |
Short-term investment funds | 363 |  |  | 279 |  |  | 84 |  |  | — |  |  | — |
Partnership interests | 120 |  |  | — |  |  | — |  |  | — |  |  | 120 |
Hedge funds | 226 |  |  | — |  |  | — |  |  | — |  |  | 226 |
Real estate limited partnerships | 144 |  |  | — |  |  | — |  |  | — |  |  | 144 |
U.S. government securities | 961 |  |  | — |  |  | 961 |  |  | — |  |  | — |
Guaranteed investment contracts | 27 |  |  | — |  |  | — |  |  | 27 |  |  | — |
Governments bonds – foreign | 30 |  |  | — |  |  | 30 |  |  | — |  |  | — |
Cash | 28 |  |  | 28 |  |  | — |  |  | — |  |  | — |
Net pending transactions and other investments | (2 | ) |  | (6 | ) |  | 4 |  |  | — |  |  | — |
Total assets(a) | $ | 8,324 |  |  | $ | 2,052 |  |  | $ | 5,133 |  |  | $ | 27 |  |  | $ | 1,112 |
(a) | Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio, Duke Energy Indiana, and Piedmont were allocated approximately 27 percent, 31 percent, 15 percent, 16 percent, 5 percent, 7 percent, and 4 percent, respectively, of the Duke Energy Master Retirement Trust at December 31, 2018. Accordingly, all amounts included in the table above are allocable to the Subsidiary Registrants using these percentages.
(b) | Certain investments that are measured at fair value using the net asset value per share practical expedient have not been categorized in the fair value hierarchy.
| December 31, 2017
| Total Fair |  |  |  |  |  |  |  |  | Not |
(in millions) | Value |  |  | Level 1 |  |  | Level 2 |  |  | Level 3 |  |  | Categorized(b) |
Equity securities | $ | 2,823 |  |  | $ | 1,976 |  |  | $ | — |  |  | $ | — |  |  | $ | 847 |
Corporate debt securities | 4,694 |  |  | — |  |  | 4,694 |  |  | — |  |  | — |
Short-term investment funds | 246 |  |  | 192 |  |  | 54 |  |  | — |  |  | — |
Partnership interests | 137 |  |  | — |  |  | — |  |  | — |  |  | 137 |
Hedge funds | 226 |  |  | — |  |  | — |  |  | — |  |  | 226 |
Real estate limited partnerships | 135 |  |  | — |  |  | — |  |  | — |  |  | 135 |
U.S. government securities | 762 |  |  | — |  |  | 762 |  |  | — |  |  | — |
Guaranteed investment contracts | 28 |  |  | — |  |  | — |  |  | 28 |  |  | — |
Governments bonds – foreign | 38 |  |  | — |  |  | 38 |  |  | — |  |  | — |
Cash | 6 |  |  | 6 |  |  | — |  |  | — |  |  | — |
Government and commercial mortgage backed securities | 2 |  |  | — |  |  | 2 |  |  | — |  |  | — |
Net pending transactions and other investments | 17 |  |  | 15 |  |  | 2 |  |  | — |  |  | — |
Total assets(a) | $ | 9,114 |  |  | $ | 2,189 |  |  | $ | 5,552 |  |  | $ | 28 |  |  | $ | 1,345 |
(a) | Duke Energy Carolinas, Progress Energy, Duke Energy Progress, Duke Energy Florida, Duke Energy Ohio, Duke Energy Indiana, and Piedmont were allocated approximately 27 percent, 30 percent, 15 percent, 15 percent, 5 percent, 8 percent, and 4 percent, respectively, of the Duke Energy Master Retirement Trust and Piedmont's Pension assets at December 31, 2017. Accordingly, all amounts included in the table above are allocable to the Subsidiary Registrants using these percentages.
(b) | Certain investments that are measured at fair value using the net asset value per share practical expedient have not been categorized in the fair value hierarchy.
The following table provides a reconciliation of beginning and ending balances of Duke Energy Master Retirement Trust qualified pension and other post-retirement assets at fair value on a recurring basis where the determination of fair value includes significant unobservable inputs (Level 3).
(in millions) | 2018 |  |  | 2017(a) |
Balance at January 1 | $ | 28 |  |  | $ | 38 |
Sales | (1 | ) |  | (2 | )
Total gains and other, net | — |  |  | 1 |
Transfer of Level 3 assets to other classifications | — |  |  | (9 | )
Balance at December 31 | $ | 27 |  |  | $ | 28 |
(a) | Balance at January 1 includes $9 million associated with Piedmont pension assets.
Other post-retirement assets The following tables provide the fair value measurement amounts for VEBA trust assets.
| December 31, 2018
| Total Fair |  |  |
(in millions) | Value |  |  | Level 2 |
Cash and cash equivalents | $ | 3 |  |  | $ | 3 |
Real estate | 1 |  |  | 1 |
Equity securities | 25 |  |  | 25 |
Debt securities | 20 |  |  | 20 |
Total assets | $ | 49 |  |  | $ | 49 |
| December 31, 2017
| Total Fair |  |  |
(in millions) | Value |  |  | Level 2 |
Cash and cash equivalents | $ | 8 |  |  | $ | 8 |
Real estate | 1 |  |  | 1 |
Equity securities | 28 |  |  | 28 |
Debt securities | 21 |  |  | 21 |
Total assets | $ | 58 |  |  | $ | 58 |
EMPLOYEE SAVINGS PLANS Retirement Savings Plan Duke Energy or its affiliates sponsor, and the Subsidiary Registrants participate in, employee savings plans that cover substantially all U.S. employees. Most employees participate in a matching contribution formula where Duke Energy provides a matching contribution generally equal to 100 percent of employee before-tax and Roth 401(k) contributions of up to 6 percent of eligible pay per pay period. Dividends on Duke Energy shares held by the savings plans are charged to retained earnings when declared and shares held in the plans are considered outstanding in the calculation of basic and diluted EPS. For new and rehired employees who are not eligible to participate in Duke Energy’s defined benefit plans, an additional employer contribution of 4 percent of eligible pay per pay period, which is subject to a three-year vesting schedule, is provided to the employee’s savings plan account. Certain Piedmont employees whose participation in a prior Piedmont defined benefit plan (that was frozen as of December 31, 2017) are eligible for employer transition credit contributions of 3 to 5 percent of eligible pay per period, for each pay period during the three-year period ending December 31, 2020. The following table includes pretax employer matching contributions made by Duke Energy and expensed by the Subsidiary Registrants.
|  |  | Duke |  |  |  |  | Duke |  |  | Duke |  |  | Duke |  |  | Duke |  |  |
| Duke |  |  | Energy |  |  | Progress |  |  | Energy |  |  | Energy |  |  | Energy |  |  | Energy |  |  |
(in millions) | Energy |  |  | Carolinas |  |  | Energy |  |  | Progress |  |  | Florida |  |  | Ohio |  |  | Indiana |  |  | Piedmont(a) |
Years ended December 31, |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
2018 | $ | 213 |  |  | $ | 68 |  |  | $ | 58 |  |  | $ | 40 |  |  | $ | 19 |  |  | $ | 4 |  |  | $ | 10 |  |  | $ | 12 |
2017 | 179 |  |  | 61 |  |  | 53 |  |  | 37 |  |  | 16 |  |  | 3 |  |  | 9 |  |  | 7 |
2016 | 169 |  |  | 57 |  |  | 50 |  |  | 35 |  |  | 15 |  |  | 3 |  |  | 8 |  |  |  |
(a) | Piedmont's pretax employer matching contributions were $1 million and $7 million during the two months ended December 31, 2016, and for the year ended October 31, 2016, respectively.
Money Purchase Pension Plan Piedmont sponsored the MPP plan, which is a defined contribution pension plan that allowed employees to direct investments and assume risk of investment returns. Under the MPP plan, Piedmont annually deposited a percentage of each participant’s pay into an account of the MPP plan. This contribution equaled 4 percent of the participant’s eligible compensation plus an additional 4 percent of eligible compensation above the Social Security wage base up to the IRS compensation limit. The participant was vested in MPP plan after three years of service. No contributions were made to the MPP plan during the two months ended December 31, 2016. Piedmont contributed $2 million to the MPP plan during each of the years ended December 31, 2017, and October 31, 2016. Effective December 31, 2017, the MPP Plan was merged into the Retirement Savings Plan and the money purchase plan formula was discontinued. Beginning with the 2018 plan year, the former MPP Plan participants are eligible to receive the additional employer contribution under the Retirement Savings Plan, discussed above.

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