capital asset purchases associated with the retail segment were $ 294 million in 2007 , bringing the total capital asset purchases since inception of the retail segment to $ 1.0 billion .as of september 29 , 2007 , the retail segment had approximately 7900 employees and had outstanding operating lease commitments associated with retail store space and related facilities of $ 1.1 billion .the company would incur substantial costs if it were to close multiple retail stores .such costs could adversely affect the company 2019s financial condition and operating results .other segments the company 2019s other segments , which consists of its asia pacific and filemaker operations , experienced an increase in net sales of $ 406 million , or 30% ( 30 % ) during 2007 compared to 2006 .this increase related primarily to a 58% ( 58 % ) increase in sales of mac portable products and strong ipod sales in the company 2019s asia pacific region .during 2006 , net sales in other segments increased 35% ( 35 % ) compared to 2005 primarily due to an increase in sales of ipod and mac portable products .strong sales growth was a result of the introduction of the updated ipods featuring video-playing capabilities and the new intel-based mac portable products that translated to a 16% ( 16 % ) increase in mac unit sales during 2006 compared to 2005 .gross margin gross margin for each of the last three fiscal years are as follows ( in millions , except gross margin percentages ) : september 29 , september 30 , september 24 , 2007 2006 2005 .
[['', 'september 29 2007', 'september 30 2006', 'september 24 2005'], ['net sales', '$ 24006', '$ 19315', '$ 13931'], ['cost of sales', '15852', '13717', '9889'], ['gross margin', '$ 8154', '$ 5598', '$ 4042'], ['gross margin percentage', '34.0% ( 34.0 % )', '29.0% ( 29.0 % )', '29.0% ( 29.0 % )']]
gross margin percentage of 34.0% ( 34.0 % ) in 2007 increased significantly from 29.0% ( 29.0 % ) in 2006 .the primary drivers of this increase were more favorable costs on certain commodity components , including nand flash memory and dram memory , higher overall revenue that provided for more leverage on fixed production costs and a higher percentage of revenue from the company 2019s direct sales channels .the company anticipates that its gross margin and the gross margins of the personal computer , consumer electronics and mobile communication industries will be subject to pressure due to price competition .the company expects gross margin percentage to decline sequentially in the first quarter of 2008 primarily as a result of the full-quarter impact of product transitions and reduced pricing that were effected in the fourth quarter of 2007 , lower sales of ilife and iwork in their second quarter of availability , seasonally higher component costs , and a higher mix of indirect sales .these factors are expected to be partially offset by higher sales of the company 2019s mac os x operating system due to the introduction of mac os x version 10.5 leopard ( 2018 2018mac os x leopard 2019 2019 ) that became available in october 2007 .the foregoing statements regarding the company 2019s expected gross margin percentage are forward-looking .there can be no assurance that current gross margin percentage will be maintained or targeted gross margin percentage levels will be achieved .in general , gross margins and margins on individual products will remain under downward pressure due to a variety of factors , including continued industry wide global pricing pressures , increased competition , compressed product life cycles , potential increases in the cost and availability of raw material and outside manufacturing services , and a potential shift in the company 2019s sales mix towards products with lower gross margins .in response to these competitive pressures , the company expects it will continue to take pricing actions with respect to its products .gross margins could also be affected by the company 2019s ability to effectively manage product quality and warranty costs and to stimulate .

Question: what was the change in cost of sales between 2007 and 2008 , in millions?15852 13717
Answer: 2135