Product Warranty and Related Liabilities

The following table summarizes activity for policy, product warranty, recall campaigns and courtesy transportation (dollars in millions):



	Six Months Ended
	June 30, 2015			June 30, 2014
Balance at beginning of period	$	9,646		$	7,601
Warranties issued and assumed in period – recall campaigns and courtesy transportation	386			2,485
Warranties issued and assumed in period – policy and product warranty	1,166			1,309
Payments	(2,106		)	(1,784		)
Adjustments to pre-existing warranties	329			889
Effect of foreign currency and other	(125		)	28
Balance at end of period	$	9,296		$	10,528

In the six months ended June 30, 2014 we recorded charges of approximately $2.5 billion in Automotive cost of sales for the recall of approximately 29 million vehicles as described in our 2014 Form 10-K. We had historically accrued estimated costs related to recall campaigns in GMNA when probable and reasonably estimable, which typically occurs once it is determined a specific recall campaign is needed and announced. During the three months ended September 30, 2014 we began accruing the costs for recall campaigns at the time of vehicle sale in GMNA.