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v3.22.1

Regulatory and Rate Matters (Tables) | 3 Months Ended
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Mar. 31, 2022
Regulated Operations [Abstract] |
Schedule of Rate Increases for Transmission Costs | The following sets forth TNMP’s recent interim transmission cost rate increases:
Effective Date |  | Approved Increase in Rate Base |  | Annual Increase in Revenue
|  | (In millions)
March 12, 2021 |  | $ | 112.6 |  |  | $ | 14.1 |
September 20, 2021 |  | $ | 41.2 |  |  | $ | 6.3 |
March 25, 2022 |  | $ | 95.6 |  |  | $ | 14.2 |

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