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Regulatory and Rate Matters (Tables)

3 Months Ended

Mar. 31, 2018

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 23, 2016		$	25.8			$	4.3
September 8, 2016		9.5				1.8
March 14, 2017		30.2				4.8
September 13, 2017		27.5				4.7
March 27, 2018		32.0				0.6

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