8. Other Income

The components of other income for the three months and six months ended June 30, 2016 and 2015 were:



	Three Months Ended June 30,				Six Months Ended June 30,
	2016		2015		2016		2015

	(in millions)
Payments for order flow	$	3	$	4	$	7	$	8
Market data fees		8		6		17		13
Account activity fees		5		4		9		8
Risk exposure fees		4		7		9		11
Gains on financial instruments, at fair value and other investments, net		16		3		51		35
Gains (losses) from currency diversification strategy, net		17		25		101		(162)
Other, net		4		6		7		10
	$	57	$	55	$	201	$	(77)

Payments for order flow are earned from various options exchanges based upon options trading volume originated by the Operating Companies. Market data fees are charged to customers based upon market data services provided and are largely offset by the related cost to obtain the underlying market data from third party vendors. Risk exposure fees are earned from a small minority of customers’ accounts with positions on which market risk exceeds certain thresholds. Gains and losses on financial instruments, at fair value and other investments include realized and unrealized gains and losses on financial instruments that are not held for the Company’s market making operations or from securities that are subject to restrictions, and the Company’s interests in the earnings of equity method investees and dividends received on cost‑basis investments.