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INCOME TAXES - Net Provisions for Income Taxes (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2015
Federal |  |  |
Current | $ 0.1 | $ 0.1 | $ (3.3)
Deferred | 67.7 | 62.0 | 58.8
Investment tax credits | (0.2) | (0.2) | (0.2)
State and local |  |  |
Current | 0.5 | 0.6 | 0.0
Deferred | 9.5 | 7.0 | 6.9
Total income tax expense | 77.6 | 69.5 | 62.2
Spire Missouri |  |  |
Federal |  |  |
Current | 0.0 | 0.0 | (2.1)
Deferred | 42.0 | 37.5 | 40.9
Investment tax credits | (0.2) | (0.2) | (0.2)
State and local |  |  |
Current | 0.0 | 0.1 | (0.1)
Deferred | 5.7 | 8.0 | 4.7
Total income tax expense | 47.5 | 45.4 | 43.2
Spire Alabama |  |  |
Federal |  |  |
Current | 0.0 | (0.8) | 0.0
Deferred | 31.6 | 29.4 | 25.9
State and local |  |  |
Current | 0.0 | 0.0 | 0.1
Deferred | 4.2 | 3.8 | 3.3
Total income tax expense | $ 35.8 | $ 32.4 | $ 29.3

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