South America sales in 2013 were significantly impacted by a weaker Brazilian real and the devaluation of the  Venezuelan  bolivar. Adjusted for currency ef fects, 2013 sales were up about 24%. Growth in medium/heavy truck production of about 28%,  an increase in light vehicle production of around 4% and the inflationary or devaluation related pricing recovery were the  principal drivers of the organic increase in sales. Asia Pacific sales were 8% lower than in 2012. Adverse currency effects resulted principally from a weakening of the  Indian rupee and Japanese yen, partially of fset by a stronger Chinese yuan. Declining economic conditions in India and  Thailand contributed to this region's reduced sales, partially of fset by stronger market volume in China. Cost of sales and gross margin  — Cost of sales for 2013 was 6% lower than in 2012, with cost of sales as a percent of sales of  86.4% being comparable with the 86.5% incurred in 2012. The reduction in cost is consistent with the decline in sales, due  principally to weaker international currencies, scheduled light vehicle program roll-of fs and lower production levels. Through  continued supplier rationalization and engineering design actions, we achieved material cost reductions of approximately $70,  which more than offset an increase in commodity costs of about $20. During the fourth quarter of 2013, we ceased production  at our foundry in Argentina. In connection therewith, we recognized $8 of accelerated depreciation expense to adjust the  foundry assets to their expected recoverable value.  The additional depreciation expense, increased engineering and product  development expense, and other inflationary increases lar gely offset the material cost savings. Gross margin of $920 in 2013 decreased $54 from 2012, representing 13.6% of sales – slightly better than last year's gross  margin percentage of 13.5%. Material cost savings of fset the margin reduction attributable to the ef fect of lower sales volumes,  inflationary increases and other costs of sales increases discussed in the preceding paragraph. Selling, general and administrative expenses (SG&A)  — SG&A expenses in 2013 were $410 (6.1% of sales) as compared to  $424 (5.9% of sales) in 2012. Salary and benefits expense in 2013 was approximately $5 less than in 2012, with the remaining  $9 reduction coming from selling expense and other discretionary spending. Restructuring charges, net  — Restructuring charges of $24 in 2013 primarily represent the impact of headcount reduction  initiatives, primarily in our Light Vehicle and Commercial Vehicle businesses in Argentina and Australia as well as in our Off- Highway business in Europe. Total restructuring charges also include severance and exit costs associated with previously  announced initiatives, offset in part by a $10 reversal of previously accrued obligations. New customer programs and other  developments in our North American Light Vehicle and Power Technologies businesses and a decision by our European Of f- Highway business to in-source the manufacturing of certain parts were the primary factors leading to the reversal of previously  accrued severance obligations. Restructuring char ges of $47 in 2012 related to work force reduction actions in certain of our  South American manufacturing operations and the realignment of certain of our North  American regional operations.  Restructuring charges in 2012 also included severance and exit costs relating to previously announced actions, including a  charge of $11 to accrue the estimated fair value of the remaining lease obligation associated with exiting our Kalamazoo,  Michigan facility. Other income, net  — The following table shows the major components of other income, net. Interest income in 2013 includes $3 from a favorable legal ruling related to recovery of gross receipts taxes paid in Brazil  in earlier periods and higher interest earned on cash deposits, partially of fset by $4 of lower interest earned on a payment-in- kind note receivable as a result of a prepayment received on the note during the second quarter of 2013.  The net foreign  exchange loss for 2013 includes a charge of $6 resulting from the devaluation of the  Venezuelan bolivar and subsequent  recoveries of $5 as the Venezuelan government allowed certain transactions existing at the date of devaluation to be settled at  26 2013 2012 Interest income $ 25 $ 24 Government grants and incentives 3 8 Foreign exchange gain (loss) (5 ) (15 ) Strategic transaction expenses (4 ) (10 ) Write-off of deferred financing costs (4 ) Gain on sale of marketable securities 9 Recognition of unrealized gain on payment-in-kind note receivable 5 Insurance and other recoveries 13 2 Impairment of long-lived assets (2 ) Other 13 12 Other income, net $ 55 $ 19