Income taxes	6 Months Ended
Jun. 30, 2011
Income taxes
Income taxes	5. Income taxes The income tax expense of $134 million for the three months ended June 30, 2011 reflected an effective tax rate of 28.6%. The effective tax rate of 28.6% for the three months ended June 30, 2011 differed from the statutory rate of 35.0% primarily due to foreign income taxes levied at relatively lower rates, geographic mix in profitability, recognition of federal and California research and development credits and federal domestic production deductions. For the six months ended June 30, 2011, the tax rate was based on our projected annual effective tax rate for 2011, and also included certain discrete tax items recorded during the period. Our tax expense of $308 million for the six months ended June 30, 2011 reflected an effective tax rate of 26.9% which differed slightly from the effective tax rate of 26.1% for the six months ended June 30, 2010, primarily due to a minor increase in the projected amount of domestic earnings with a higher statutory rate, relative to earnings in foreign jurisdictions with a lower statutory rate. The overall effective income tax rate for the year could be different from the effective tax rate for the three and six months ended June 30, 2011 and will be dependent, in part, on our profitability for the remainder of the year. In addition, our effective income tax rates for the remainder of 2011 and future periods will depend on a variety of factors, such as changes in the mix of income by tax jurisdiction, applicable accounting rules, applicable tax laws and regulations, rulings and interpretations thereof, developments in tax audit and other matters, and variations in the estimated and actual level of annual pre-tax income or loss. Further, the effective tax rate could fluctuate significantly on a quarterly basis and could be adversely affected by the extent that income (loss) before income tax expenses (benefit) is lower than anticipated in foreign regions where taxes are levied at lower statutory rates and/or higher than anticipated in our domestic region where taxes are levied at higher statutory rates.

Income taxes

6 Months Ended

Jun. 30, 2011

5. Income taxes

The income tax expense of $134 million for the three months ended June 30, 2011 reflected an effective tax rate of 28.6%. The effective tax rate of 28.6% for the three months ended June 30, 2011 differed from the statutory rate of 35.0% primarily due to foreign income taxes levied at relatively lower rates, geographic mix in profitability, recognition of federal and California research and development credits and federal domestic production deductions.

For the six months ended June 30, 2011, the tax rate was based on our projected annual effective tax rate for 2011, and also included certain discrete tax items recorded during the period. Our tax expense of $308 million for the six months ended June 30, 2011 reflected an effective tax rate of 26.9% which differed slightly from the effective tax rate of 26.1% for the six months ended June 30, 2010, primarily due to a minor increase in the projected amount of domestic earnings with a higher statutory rate, relative to earnings in foreign jurisdictions with a lower statutory rate.

The overall effective income tax rate for the year could be different from the effective tax rate for the three and six months ended June 30, 2011 and will be dependent, in part, on our profitability for the remainder of the year. In addition, our effective income tax rates for the remainder of 2011 and future periods will depend on a variety of factors, such as changes in the mix of income by tax jurisdiction, applicable accounting rules, applicable tax laws and regulations, rulings and interpretations thereof, developments in tax audit and other matters, and variations in the estimated and actual level of annual pre-tax income or loss. Further, the effective tax rate could fluctuate significantly on a quarterly basis and could be adversely affected by the extent that income (loss) before income tax expenses (benefit) is lower than anticipated in foreign regions where taxes are levied at lower statutory rates and/or higher than anticipated in our domestic region where taxes are levied at higher statutory rates.