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NSTAR ELECTRIC COMPANY AND SUBSIDIARY CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Operating Revenues | $ 9,863,085 | $ 8,904,430 | $ 8,526,470
Operating Expenses: |  |  |
Purchased Power and Transmission | 3,372,344 | 2,987,840 | 3,040,160
Operations and Maintenance | 1,739,685 | 1,480,252 | 1,363,113
Depreciation | 1,103,008 | 981,380 | 885,278
Amortization of Regulatory Assets, Net | 231,965 | 177,679 | 195,380
Energy Efficiency Programs | 592,775 | 535,760 | 501,369
Taxes Other Than Income Taxes | 829,987 | 752,785 | 711,035
Total Operating Expenses | 7,869,764 | 6,915,696 | 6,935,979
Operating Income | 1,993,321 | 1,988,734 | 1,590,491
Interest Expense | 582,334 | 538,452 | 533,197
Other Income, Net | 161,282 | 108,590 | 132,777
Income Before Income Tax Expense | 1,572,269 | 1,558,872 | 1,190,071
Income Tax Expense | 344,223 | 346,186 | 273,499
Net Income | 1,228,046 | 1,212,686 | 916,572
NSTAR Electric Company |  |  |
Operating Revenues | 3,056,350 | 2,941,148 | 3,044,642
Operating Expenses: |  |  |
Purchased Power and Transmission | 932,530 | 879,244 | 1,064,289
Operations and Maintenance | 563,172 | 534,118 | 468,436
Depreciation | 337,451 | 319,468 | 296,500
Amortization of Regulatory Assets, Net | 55,774 | 83,248 | 103,735
Energy Efficiency Programs | 288,612 | 263,986 | 289,206
Taxes Other Than Income Taxes | 216,703 | 206,764 | 195,586
Total Operating Expenses | 2,394,242 | 2,286,828 | 2,417,752
Operating Income | 662,108 | 654,320 | 626,890
Interest Expense | 146,048 | 130,508 | 114,198
Other Income, Net | 74,844 | 52,017 | 44,577
Income Before Income Tax Expense | 590,904 | 575,829 | 557,269
Income Tax Expense | 114,335 | 130,828 | 125,313
Net Income | $ 476,569 | $ 445,001 | $ 431,956

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