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CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDERS' EQUITY - USD ($) $ in Millions | Total | Common Stock Outstanding | Paid-in Capital | Retained Earnings | AOCI | Spire Missouri | Spire Missouri Common Stock Outstanding | Spire Missouri Paid-in Capital | Spire Missouri Retained Earnings | Spire Missouri AOCI | Spire Alabama | Spire Alabama Common Stock Outstanding | Spire Alabama Paid-in Capital | Spire Alabama Retained Earnings
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
BALANCE (in shares) at Sep. 30, 2014 |  | 43,178,405 |  |  |  |  | 24,577 |  |  |  |  | 1,972,052 |  |
BALANCE at Sep. 30, 2014 | $ 1,508.4 | $ 43.2 | $ 1,029.4 | $ 437.5 | $ (1.7) | $ 1,007.8 | $ 0.1 | $ 744.0 | $ 265.6 | $ (1.9) | $ 849.6 | $ 0.0 | $ 503.9 | $ 345.7
Stockholders' Equity Rollforward |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | 136.9 |  |  | 136.9 |  | 105.3 |  |  | 105.3 |  | 48.0 |  |  | 48.0
Purchase accounting adjustments |  |  |  |  |  |  |  |  |  |  | 4.0 |  | 4.0 |
Common stock offering (in shares) |  |  |  |  |  |  |  |  |  |  |  | 0 |  |
Common stock offering |  |  |  |  |  |  |  |  |  |  | (27.0) |  | (27.0) |
Dividend reinvestment plan (in shares) |  | 31,166 |  |  |  |  |  |  |  |  |  |  |  |
Dividend reinvestment plan | 1.6 | $ 0.0 | 1.6 |  |  |  |  |  |  |  |  |  |  |
Stock-based compensation costs | 6.7 |  | 6.7 |  |  | 3.7 |  | 3.7 |  |  |  |  |  |
Stock issued under stock-based compensation plans (in shares) |  | 156,925 |  |  |  |  |  |  |  |  |  |  |  |
Stock issued under stock-based compensation plans | 1.4 | $ 0.1 | 1.3 |  |  |  |  |  |  |  |  |  |  |
Employees’ tax withholding for stock-based compensation (in shares) |  | (31,484) |  |  |  |  |  |  |  |  |  |  |  |
Employees’ tax withholding for stock-based compensation | (1.6) |  | (1.6) |  |  |  |  |  |  |  |  |  |  |
Tax benefit - stock compensation | 0.7 |  | 0.7 |  |  | 0.5 |  | 0.5 |  |  |  |  |  |
Dividends declared | (80.2) |  |  | (80.2) |  | (79.7) |  |  | (79.7) |  |  |  |  |
Other comprehensive loss, net of tax | (0.3) |  |  |  | (0.3) | 0.2 |  |  |  | 0.2 |  |  |  |
BALANCE (in shares) at Sep. 30, 2015 |  | 43,335,012 |  |  |  |  | 24,577 |  |  |  |  | 1,972,052 |  |
BALANCE at Sep. 30, 2015 | 1,573.6 | $ 43.3 | 1,038.1 | 494.2 | (2.0) | 1,037.8 | $ 0.1 | 748.2 | 291.2 | (1.7) | 874.6 | $ 0.0 | 480.9 | 393.7
Stockholders' Equity Rollforward |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | 144.2 |  |  | 144.2 |  | 105.9 |  |  | 105.9 |  | 53.2 |  |  | 53.2
Common stock offering (in shares) |  | 2,185,000 |  |  |  |  |  |  |  |  |  |  |  |
Common stock offering | 133.2 | $ 2.2 | 131.0 |  |  |  |  |  |  |  |  |  |  |
Dividend reinvestment plan (in shares) |  | 22,878 |  |  |  |  |  |  |  |  |  |  |  |
Dividend reinvestment plan | 1.4 |  | 1.4 |  |  |  |  |  |  |  |  |  |  |
Stock-based compensation costs | 6.7 |  | 6.7 |  |  | 3.7 |  | 3.7 |  |  |  |  |  |
Stock issued under stock-based compensation plans (in shares) |  | 136,979 |  |  |  |  |  |  |  |  |  |  |  |
Stock issued under stock-based compensation plans | 0.5 | $ 0.1 | 0.4 |  |  |  |  |  |  |  |  |  |  |
Employees’ tax withholding for stock-based compensation (in shares) |  | (29,227) |  |  |  |  |  |  |  |  |  |  |  |
Employees’ tax withholding for stock-based compensation | (1.7) |  | (1.7) |  |  |  |  |  |  |  |  |  |  |
Dividends declared | (87.5) |  |  | (87.5) |  | (78.8) |  |  | (78.8) |  |  |  |  |
Return of capital to Spire |  |  |  |  |  |  |  |  |  |  | (29.0) |  | (29.0) |
Other comprehensive loss, net of tax | (2.2) |  |  |  | (2.2) | (0.1) |  |  |  | (0.1) |  |  |  |
BALANCE (in shares) at Sep. 30, 2016 |  | 45,650,642 |  |  |  |  | 24,577 |  |  |  |  | 1,972,052 |  |
BALANCE at Sep. 30, 2016 | 1,768.2 | $ 45.6 | 1,175.9 | 550.9 | (4.2) | 1,068.5 | $ 0.1 | 751.9 | 318.3 | (1.8) | 867.3 | $ 0.0 | 451.9 | 415.4
Stockholders' Equity Rollforward |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net income | 161.6 |  |  | 161.6 |  | 113.0 |  |  | 113.0 |  | 58.1 |  |  | 58.1
Common stock offering (in shares) |  | 2,504,684 |  |  |  |  |  |  |  |  |  |  |  |
Common stock offering | 145.5 | $ 2.5 | 143.0 |  |  |  |  |  |  |  |  |  |  |
Dividend reinvestment plan (in shares) |  | 23,731 |  |  |  |  |  |  |  |  |  |  |  |
Dividend reinvestment plan | 1.6 |  | 1.6 |  |  |  |  |  |  |  |  |  |  |
Stock-based compensation costs |  |  |  |  |  | 4.2 |  | 4.2 |  |  |  |  |  |
Stock issued under stock-based compensation plans (in shares) |  | 119,700 |  |  |  |  |  |  |  |  |  |  |  |
Stock issued under stock-based compensation plans | 0.1 | $ 0.2 | (0.1) |  |  |  |  |  |  |  |  |  |  |
Employees’ tax withholding for stock-based compensation (in shares) |  | (35,514) |  |  |  |  |  |  |  |  |  |  |  |
Employees’ tax withholding for stock-based compensation | (2.2) |  | (2.2) |  |  |  |  |  |  |  |  |  |  |
Dividends declared | (99.2) |  |  | (99.2) |  | (14.8) |  |  | (14.8) |  | (27.0) |  |  | (27.0)
Return of capital to Spire |  |  |  |  |  |  |  |  |  |  | (31.0) |  | (31.0) |
Other comprehensive loss, net of tax | 7.4 |  |  |  | 7.4 | 0.1 |  |  |  | 0.1 |  |  |  |
BALANCE (in shares) at Sep. 30, 2017 |  | 48,263,243 |  |  |  |  | 24,577 |  |  |  |  | 1,972,052 |  |
BALANCE at Sep. 30, 2017 | 1,991.3 | $ 48.3 | 1,325.6 | 614.2 | $ 3.2 | $ 1,171.0 | $ 0.1 | $ 756.1 | $ 416.5 | $ (1.7) | $ 867.4 | $ 0.0 | $ 420.9 | $ 446.5
Stockholders' Equity Rollforward |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-based compensation costs (After Adoption) | $ 8.3 |  | $ 7.4 | $ 0.9 |  |  |  |  |  |  |  |  |  |

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