Revenue

The following table disaggregates our revenue by major source for revenue generating segments:



	Three Months Ended June 30, 2018
	GMNA		GMI		Corporate		Total Automotive		GM Financial		Eliminations			Total
Vehicle, parts and accessories	$	26,874	$	4,489	$	1	$	31,364	$	—	$	(18	)	$	31,346
Used vehicles	769		68		—		837		—		(16		)	821
Services and other	858		201		49		1,108		—		—			1,108
Automotive net sales and revenue	28,501		4,758		50		33,309		—		(34		)	33,275
Leased vehicle income	—		—		—		—		2,497		—			2,497
Finance charge income	—		—		—		—		884		(1		)	883
Other income	—		—		—		—		107		(2		)	105
GM Financial net sales and revenue	—		—		—		—		3,488		(3		)	3,485
Net sales and revenue	$	28,501	$	4,758	$	50	$	33,309	$	3,488	$	(37	)	$	36,760



	Six Months Ended June 30, 2018
	GMNA		GMI		Corporate		Total Automotive		GM Financial		Eliminations			Total
Vehicle, parts and accessories	$	52,756	$	9,094	$	10	$	61,860	$	—	$	(25	)	$	61,835
Used vehicles	1,924		115		—		2,039		—		(33		)	2,006
Services and other	1,639		397		89		2,125		—		—			2,125
Automotive net sales and revenue	56,319		9,606		99		66,024		—		(58		)	65,966
Leased vehicle income	—		—		—		—		4,944		—			4,944
Finance charge income	—		—		—		—		1,750		(3		)	1,747
Other income	—		—		—		—		205		(3		)	202
GM Financial net sales and revenue	—		—		—		—		6,899		(6		)	6,893
Net sales and revenue	$	56,319	$	9,606	$	99	$	66,024	$	6,899	$	(64	)	$	72,859

Revenue is measured as the amount of consideration we expect to receive in exchange for transferring goods or providing services. Adjustments to sales incentives for previously recognized sales decreased revenue by $482 million and $628 million during the three and six months ended June 30, 2018.

Deferred revenue consists primarily of maintenance, extended warranty and other service contracts. We recognized revenue of $402 million and $785 million related to previously deferred revenue during the three and six months ended June 30, 2018. We expect to recognize revenue of $845 million in the six months ending December 31, 2018 and $885 million, $450 million and $569 million in the years ending December 31, 2019, 2020 and thereafter related to deferred revenue as of June 30, 2018.