product transitions and expected increases in the cost of key components including but not limited to microprocessors, NAND flash memory, dynamic random access memory (“DRAM”) and liquid crystal displays (“LCDs”), as well as potential increases in the costs of outside manufacturing services and a potential shift in the Company’s sales mix towards products with lower gross margins. In response to these competitive pressures, the Company expects it will continue to take product pricing actions, which would adversely affect gross margins. Gross margins could also be affected by the Company’s ability to manage product quality and warranty costs effectively and to stimulate demand for certain of its products. Due to the Company’s significant international operations, financial results can be significantly affected in the short-term by fluctuations in exchange rates.

Research and Development (“R&D”)

R&D expenditures increased 20% or $224 million to $1.3 billion in 2009 compared to 2008. These increases were due primarily to an increase in headcount and higher stock-based compensation expenses in the current year to support expanded R&D activities. In addition, $71 million of software development costs were capitalized related to Mac OS X Snow Leopard and excluded from R&D expense during 2009, compared to $11 million of software development costs capitalized during 2008. Although total R&D expense increased 20% during 2009, it remained relatively flat as a percentage of net sales given the 12% increase in revenue in 2009. The Company continues to believe that focused investments in R&D are critical to its future growth and competitive position in the marketplace and are directly related to timely development of new and enhanced products that are central to the Company’s core business strategy. As such, the Company expects to make further investments in R&D to remain competitive.

Expenditures for R&D increased 42% or $327 million to $1.1 billion in 2008 compared to 2007. These increases were due primarily to an increase in headcount in 2008 and higher stock-based compensation expenses. In 2008, $11 million of software development costs were capitalized related to Mac OS X Snow Leopard and excluded from R&D expense, while R&D expense for 2007 excluded $75 million of capitalized software development costs related to Mac OS X Leopard and iPhone software. Although total R&D expense increased 42% during 2008, it remained relatively flat as a percentage of net sales given the 35% increase in revenue during 2008.

Selling, General and Administrative Expense (“SG&A”)

SG&A expenditures increased $388 million or 10% to $4.1 billion in 2009 compared to 2008. These increases are due primarily to the Company’s continued expansion of its Retail segment in both domestic and international markets, higher stock-based compensation expenses and higher spending on marketing and advertising.

Expenditures for SG&A increased $798 million or 27% to $3.8 billion in 2008 compared to 2007. These increases are due primarily to higher stock-based compensation expenses, higher variable selling expenses resulting from the significant year-over-year increase in total net