10. Revenue

The following disaggregates TEC’s revenue by major source for the three and six months ended June 30, 2018:

(millions)	Tampa							Tampa Electric
Three months ended June 30, 2018	Electric		PGS		Eliminations			Company
Electric revenue
Residential	$	241	$	0	$	0		$	241
Commercial		140		0		0			140
Industrial		40		0		0			40
Regulatory deferrals and unbilled revenue		24		0		0			24
Other ⁽¹⁾		65		0		(1	)		64
Total electric revenue		510		0		(1	)		509
Gas revenue
Residential		0		35		0			35
Commercial		0		37		0			37
Industrial ⁽²⁾		0		6		0			6
Other ⁽³⁾		0		37		(5	)		32
Total gas revenue		0		115		(5	)		110
Total revenue	$	510	$	115	$	(6	)	$	619
Six months ended June 30, 2018
Electric revenue
Residential	$	471	$	0	$	0		$	471
Commercial		272		0		0			272
Industrial		78		0		0			78
Regulatory deferrals and unbilled revenue		23		0		0			23
Other ⁽¹⁾		127		0		(1	)		126
Total electric revenue		971		0		(1	)		970
Gas revenue
Residential		0		91		0			91
Commercial		0		81		0			81
Industrial ⁽²⁾		0		11		0			11
Other ⁽³⁾		0		74		(11	)		63
Total gas revenue		0		257		(11	)		246
Total revenue	$	971	$	257	$	(12	)	$	1,216

(1) Other includes sales to public authorities, off-system sales to other utilities and various other items.

(2) Industrial includes sales to power generation customers.

(3) Other includes off-system sales to other utilities and various other items.

Remaining Performance Obligations

Remaining performance obligations primarily represent lighting contracts and gas transportation contracts with fixed contract terms. As of June 30, 2018, the aggregate amount of the transaction price allocated to remaining performance obligations was approximately $140 million. As allowed by the practical expedient in ASC 606, this amount excludes contracts with an original expected length of one year or less and variable amounts for which TEC recognizes revenue at the amount to which it has the right to invoice for services performed. TEC expects to recognize revenue for the remaining performance obligations through 2033.