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INVESTMENT IN TRANSMISSION AFFILIATES (Tables) | 9 Months Ended
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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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