All revenue recognized in the condensed consolidated statements of income is considered to be revenue from contracts with customers. The following table depicts the disaggregation of revenue according to product line and segment (in millions):


											Corporate
			U.S.				European		Global		Items and
	Options		Equities		Futures		Equities		FX		Eliminations		Total
Three Months Ended June 30, 2020
Transaction fees	$	250.8	$	325.1	$	15.8	$	15.2	$	11.4	$	—	$	618.3
Access and capacity fees		23.9		20.9		4.1		4.7		2.1		—		55.7
Market data fees		17.8		35.8		1.7		3.2		0.2		—		58.7
Regulatory fees		21.0		107.7		—		—		—		—		128.7
Other revenue		4.1		1.0		—		2.2		—		—		7.3
	$	317.6	$	490.5	$	21.6	$	25.3	$	13.7	$	—	$	868.7
Timing of revenue recognition
Services transferred at a point in time	$	275.9	$	433.8	$	15.8	$	17.4	$	11.4	$	—	$	754.3
Services transferred over time		41.7		56.7		5.8		7.9		2.3		—		114.4
	$	317.6	$	490.5	$	21.6	$	25.3	$	13.7	$	—	$	868.7

Three Months Ended June 30, 2019
Transaction fees	$	185.9	$	182.0	$	28.3	$	19.5	$	11.2	$	—	$	426.9
Access and capacity fees		25.6		19.6		3.8		3.9		1.6		—		54.5
Market data fees		14.0		32.8		1.6		3.2		0.2		—		51.8
Regulatory fees		16.7		63.0		—		—		—		—		79.7
Other revenue		3.9		1.3		0.1		2.1		0.1		0.2		7.7
	$	246.1	$	298.7	$	33.8	$	28.7	$	13.1	$	0.2	$	620.6
Timing of revenue recognition
Services transferred at a point in time	$	206.5	$	246.3	$	28.4	$	21.6	$	11.3	$	0.2	$	514.3
Services transferred over time		39.6		52.4		5.4		7.1		1.8		—		106.3
	$	246.1	$	298.7	$	33.8	$	28.7	$	13.1	$	0.2	$	620.6


											Corporate
			U.S.				European		Global		Items and
	Options		Equities		Futures		Equities		FX		Eliminations		Total
Six Months Ended June 30, 2020
Transaction fees	$	535.0	$	629.1	$	51.7	$	37.5	$	26.5	$	—	$	1,279.8
Access and capacity fees		51.1		40.9		8.1		9.6		3.7		—		113.4
Market data fees		35.0		69.8		3.3		6.4		0.4		—		114.9
Regulatory fees		43.3		222.2		—		—		—		—		265.5
Other revenue		9.7		2.2		—		4.7		—		—		16.6
	$	674.1	$	964.2	$	63.1	$	58.2	$	30.6	$	—	$	1,790.2
Timing of revenue recognition
Services transferred at a point in time	$	588.0	$	853.5	$	51.7	$	42.2	$	26.5	$	—	$	1,561.9
Services transferred over time		86.1		110.7		11.4		16.0		4.1		—		228.3
	$	674.1	$	964.2	$	63.1	$	58.2	$	30.6	$	—	$	1,790.2

Six Months Ended June 30, 2019
Transaction fees	$	358.6	$	380.9	$	52.9	$	40.6	$	23.2	$	—	$	856.2
Access and capacity fees		51.6		38.6		7.5		7.9		3.3		—		108.9
Market data fees		27.7		65.7		3.3		6.4		0.3		—		103.4
Regulatory fees		31.2		106.7		0.5		—		—		—		138.4
Other revenue		8.0		2.6		0.1		4.1		0.2		0.2		15.2
	$	477.1	$	594.5	$	64.3	$	59.0	$	27.0	$	0.2	$	1,222.1
Timing of revenue recognition
Services transferred at a point in time	$	397.8	$	490.2	$	53.5	$	44.7	$	23.4	$	0.2	$	1,009.8
Services transferred over time		79.3		104.3		10.8		14.3		3.6		—		212.3
	$	477.1	$	594.5	$	64.3	$	59.0	$	27.0	$	0.2	$	1,222.1

Contract liabilities as of June 30, 2020 primarily represent prepayments of transaction fees and certain access and capacity and market data fees to the Exchanges. The revenue recognized from contract liabilities and the remaining balance is shown below (in millions):


	Balance at January 1, 2020		Cash Additions		Revenue Recognition		Balance at June 30, 2020
Liquidity provider sliding scale (1)	$	—	$	9.6	$	(4.8)	$	4.8
Other, net		4.5		24.0		(15.8)		12.7
Total deferred revenue	$	4.5	$	33.6	$	(20.6)	$	17.5

(1)

Liquidity providers are eligible to participate in the sliding scale program, which involves prepayment of transaction fees, and to receive reduced fees based on the achievement of certain volume thresholds within a calendar month. These transaction fees are amortized and recorded ratably as the transactions occur over the period.