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CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Mar. 31, 2021 | Mar. 31, 2020
Net Income | $ 187.4 | $ 133.6 | $ 276.3 | $ 200.6
Cash flow hedging derivative instruments: |  |  |  |
Net hedging gain (loss) arising during the period | 43.5 | (41.1) | 60.7 | (22.2)
Amounts reclassified into net income | (0.4) | (2.2) | (0.7) | (2.5)
Net gain (loss) on cash flow hedging derivative instruments | 43.1 | (43.3) | 60.0 | (24.7)
Net gain (loss) on defined benefit pension and other postretirement plans | 0.2 | (0.1) | 0.2 | (0.1)
Net unrealized loss on available for sale securities | (0.1) |  | (0.1) |
Other Comprehensive Income (Loss), Before Tax | 43.2 | (43.4) | 60.1 | (24.8)
Income Tax Expense (Benefit) Related to Items of Other Comprehensive Income | 9.8 | (9.7) | 13.6 | (5.5)
Other Comprehensive Income (Loss), Net of Tax | 33.4 | (33.7) | 46.5 | (19.3)
Comprehensive Income | 220.8 | 99.9 | 322.8 | 181.3
Operating Revenues | 1,104.9 | 715.5 | 1,617.5 | 1,282.4
Operating Expenses: |  |  |  |
Natural gas | 619.1 | 297.1 | 800.3 | 559.0
Operation and maintenance | 119.0 | 105.7 | 230.6 | 222.3
Depreciation and amortization | 51.5 | 49.2 | 102.3 | 96.7
Taxes, other than income taxes | 57.9 | 53.0 | 94.0 | 91.6
Total Operating Expenses | 847.5 | 505.0 | 1,227.2 | 969.6
Operating Income | 257.4 | 210.5 | 390.3 | 312.8
Interest Expense, Net | 25.8 | 27.2 | 51.5 | 53.9
Other Income (Expense), Net | 1.8 | (19.5) | 6.1 | (13.8)
Income Before Income Taxes | 233.4 | 163.8 | 344.9 | 245.1
Income Tax Expense | 46.0 | 30.2 | 68.6 | 44.5
Spire Missouri |  |  |  |
Net Income | 93.1 | 74.5 | 149.7 | 122.5
Cash flow hedging derivative instruments: |  |  |  |
Other Comprehensive Income (Loss), Net of Tax | 0.1 | (0.2) | 0.2 | (0.1)
Comprehensive Income | 93.2 | 74.3 | 149.9 | 122.4
Operating Revenues | 790.9 | 457.5 | 1,146.4 | 831.5
Operating Expenses: |  |  |  |
Natural gas | 537.4 | 223.6 | 699.0 | 409.4
Operation and maintenance | 62.8 | 50.8 | 125.7 | 116.3
Depreciation and amortization | 31.0 | 29.3 | 61.4 | 58.3
Taxes, other than income taxes | 38.9 | 36.1 | 64.0 | 62.8
Total Operating Expenses | 670.1 | 339.8 | 950.1 | 646.8
Operating Income | 120.8 | 117.7 | 196.3 | 184.7
Interest Expense, Net | 11.7 | 12.7 | 23.4 | 25.9
Other Income (Expense), Net | 0.8 | (20.9) | 3.5 | (19.9)
Income Before Income Taxes | 109.9 | 84.1 | 176.4 | 138.9
Income Tax Expense | $ 16.8 | $ 9.6 | $ 26.7 | $ 16.4

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