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Condensed Statements of Common Stockholders' Equity (Unaudited) - MPC - USD ($) shares in Millions, $ in Millions | Total | Common Stock | Paid-In Capital | Retained Earnings (Accumulated Deficit) | Mississippi Power | Mississippi Power Common Stock | Mississippi Power Paid-In Capital | Mississippi Power Retained Earnings (Accumulated Deficit)
--- | --- | --- | --- | --- | --- | --- | --- | ---
Beginning balance (in shares) at Dec. 31, 2021 |  |  |  |  |  | 1 |  |
Beginning balance at Dec. 31, 2021 | $ 32,276 | $ 5,279 | $ 11,950 | $ 10,929 | $ 1,867 | $ 38 | $ 4,582 | $ (2,753)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net income |  |  |  |  | 42 |  |  | 42
Capital contributions from parent company |  |  |  |  | 51 |  | 51 |
Cash dividends on common stock | (702) |  |  | (702) | (43) |  |  | (43)
Ending balance (in shares) at Mar. 31, 2022 |  |  |  |  |  | 1 |  |
Ending balance at Mar. 31, 2022 | 32,629 | 5,286 | 11,994 | 11,261 | 1,917 | $ 38 | 4,633 | (2,754)
Beginning balance (in shares) at Dec. 31, 2021 |  |  |  |  |  | 1 |  |
Beginning balance at Dec. 31, 2021 | 32,276 | 5,279 | 11,950 | 10,929 | 1,867 | $ 38 | 4,582 | (2,753)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net income | 2,139 |  |  |  |  |  |  |
Ending balance (in shares) at Jun. 30, 2022 |  |  |  |  |  | 1 |  |
Ending balance at Jun. 30, 2022 | 33,013 | 5,288 | 12,033 | 11,645 | 1,921 | $ 38 | 4,634 | (2,751)
Beginning balance (in shares) at Mar. 31, 2022 |  |  |  |  |  | 1 |  |
Beginning balance at Mar. 31, 2022 | 32,629 | 5,286 | 11,994 | 11,261 | 1,917 | $ 38 | 4,633 | (2,754)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net income | 1,107 |  |  |  | 45 |  |  | 45
Capital contributions from parent company |  |  |  |  | 1 |  | 1 |
Cash dividends on common stock | (723) |  |  | (723) | (42) |  |  | (42)
Ending balance (in shares) at Jun. 30, 2022 |  |  |  |  |  | 1 |  |
Ending balance at Jun. 30, 2022 | 33,013 | 5,288 | 12,033 | 11,645 | 1,921 | $ 38 | 4,634 | (2,751)
Beginning balance (in shares) at Dec. 31, 2022 |  |  |  |  |  | 1 |  |
Beginning balance at Dec. 31, 2022 | 34,532 | 5,417 | 13,673 | 11,538 | 1,931 | $ 38 | 4,652 | (2,759)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net income |  |  |  |  | 58 |  |  | 58
Cash dividends on common stock | (742) |  |  | (742) | (46) |  |  | (46)
Ending balance (in shares) at Mar. 31, 2023 |  |  |  |  |  | 1 |  |
Ending balance at Mar. 31, 2023 | 34,562 | 5,421 | 13,715 | 11,658 | 1,943 | $ 38 | 4,652 | (2,747)
Beginning balance (in shares) at Dec. 31, 2022 |  |  |  |  |  | 1 |  |
Beginning balance at Dec. 31, 2022 | 34,532 | 5,417 | 13,673 | 11,538 | 1,931 | $ 38 | 4,652 | (2,759)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net income | 1,700 |  |  |  |  |  |  |
Ending balance (in shares) at Jun. 30, 2023 |  |  |  |  |  | 1 |  |
Ending balance at Jun. 30, 2023 | 34,648 | 5,422 | 13,742 | 11,732 | 1,948 | $ 38 | 4,664 | (2,754)
Beginning balance (in shares) at Mar. 31, 2023 |  |  |  |  |  | 1 |  |
Beginning balance at Mar. 31, 2023 | 34,562 | 5,421 | 13,715 | 11,658 | 1,943 | $ 38 | 4,652 | (2,747)
Increase (Decrease) in Stockholders' Equity [Roll Forward] |  |  |  |  |  |  |  |
Net income | 838 |  |  |  | 40 |  |  | 40
Capital contributions from parent company |  |  |  |  | 12 |  | 12 |
Cash dividends on common stock | (764) |  |  | (764) | (47) |  |  | (47)
Ending balance (in shares) at Jun. 30, 2023 |  |  |  |  |  | 1 |  |
Ending balance at Jun. 30, 2023 | $ 34,648 | $ 5,422 | $ 13,742 | $ 11,732 | $ 1,948 | $ 38 | $ 4,664 | $ (2,754)

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