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INVESTMENT IN TRANSMISSION AFFILIATES (Tables)

9 Months Ended

Sep. 30, 2025

Transmission Affiliates

Investment in transmission affiliates

Schedule of changes to our investments in transmission affiliates

The following tables provide a reconciliation of the changes in our investments in ATC and ATC Holdco:

						Three Months Ended September 30, 2025
(in millions)						ATC						ATC Holdco						Total
Balance at beginning of period						$	2,177.5					$	22.6					$	2,200.1
Add: Earnings from equity method investment						54.2						0.6						54.8
Add: Capital contributions						54.6						—						54.6
Less: Distributions						40.7						—						40.7
Balance at end of period						$	2,245.6					$	23.2					$	2,268.8
						Three Months Ended September 30, 2024
(in millions)						ATC						ATC Holdco						Total
Balance at beginning of period						$	2,029.7					$	26.1					$	2,055.8
Add: Earnings from equity method investment						46.1						0.6						46.7
Add: Capital contributions						15.2						—						15.2
Less: Distributions						37.0						—						37.0
Add: Other						0.1						—						0.1
Balance at end of period						$	2,054.1					$	26.7					$	2,080.8
						Nine Months Ended September 30, 2025
(in millions)						ATC						ATC Holdco						Total
Balance at beginning of period						$	2,085.1					$	23.8					$	2,108.9
Add: Earnings from equity method investment						154.5						5.8						160.3
Add: Capital contributions						142.4						—						142.4
Less: Distributions						136.4						6.4						142.8
Balance at end of period						$	2,245.6					$	23.2					$	2,268.8
						Nine Months Ended September 30, 2024
(in millions)						ATC						ATC Holdco						Total
Balance at beginning of period						$	1,980.8					$	25.1					$	2,005.9
Add: Earnings from equity method investment						136.7						1.6						138.3
Add: Capital contributions						45.5						—						45.5
Less: Distributions						109.0						—						109.0
Add: Other						0.1						—						0.1
Balance at end of period						$	2,054.1					$	26.7					$	2,080.8

ATC

Investment in transmission affiliates

Schedule of significant related party transactions with ATC

The following table summarizes our significant related party transactions with ATC:

						Three Months Ended September 30												Nine Months Ended September 30
(in millions)						2025						2024						2025						2024
Charges to ATC for services and construction						$	4.2					$	4.5					$	13.7					$	15.5
Charges from ATC for network transmission services						116.8						103.4						350.2						309.9
Refund from ATC related to FERC ROE orders						2.1						—						3.8						—

Schedule of receivables and payables with ATC

Our balance sheets included the following receivables and payables for services provided to or received from ATC:

(in millions)						September 30, 2025						December 31, 2024
Accounts receivable for services provided to ATC						$	1.7					$	1.4
Accounts payable for services received from ATC						38.4						34.4
Amounts due from ATC for transmission infrastructure upgrades (1)						20.9						54.5

(1)These transmission infrastructure upgrades were primarily related to the construction of WE's, WPS's, and UMERC's renewable energy projects.

Schedule of summarized income statement data for ATC

Summarized financial data for ATC is included in the tables below:

						Three Months Ended September 30												Nine Months Ended September 30
(in millions)						2025						2024						2025						2024
Income statement data
Operating revenues						$	245.1					$	221.4					$	721.2					$	651.6
Operating expenses						116.9						110.1						351.2						324.1
Other expense, net						41.4						36.4						123.2						107.4
Net income						$	86.8					$	74.9					$	246.8					$	220.1

Schedule of summarized balance sheet data for ATC

(in millions)						September 30, 2025						December 31, 2024
Balance sheet data
Current assets						$	141.5					$	126.6
Noncurrent assets						7,348.8						6,792.6
Total assets						$	7,490.3					$	6,919.2
Current liabilities						$	772.6					$	482.4
Long-term debt						3,031.6						3,083.4
Other noncurrent liabilities						613.1						545.0
Members' equity						3,073.0						2,808.4
Total liabilities and members' equity						$	7,490.3					$	6,919.2

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