The difference between the effective tax rate reflected in the provision for income taxes and the U.S. federal statutory rate of 35% was as follows (in millions):


	Three Months Ended						Six Months Ended
	June 30,						June 30,
	2016			2015			2016			2015
Federal income tax at U.S. federal statutory rate	$	(118	)	$	137		$	(201	)	$	313
Foreign income tax rate differential		3			(41	)		(24	)		(87	)
State income tax, net of federal benefit		(1	)		—			(5	)		3
Nondeductible expenses		9			12			21			17
Tax benefit of manufacturing deduction		—			—			—			(10	)
Foreign dividends, net of foreign tax credits		(24	)		8			(19	)		15
Tax impact of foreign exchange		1			(19	)		(7	)		(18	)
Change in valuation allowance		11			3			21			6
Tax rate change on temporary differences		(5	)		1			(3	)		(3	)
Change in tax reserves		3			—			(20	)		69
Other		—			4			(2	)		(11	)

Provision for income taxes	$	(121	)	$	105		$	(239	)	$	294