Income Tax Expense

6 Months Ended

Jun. 30, 2011

Income Tax Expense

Income Tax Expense

Note 8. Income Tax Expense

Our income tax expense was $16.9 million and $18.4 million for the quarters ended June 30, 2011 and 2010, respectively and $40.8 million and $32.3 million for the six months ended June 30, 2011 and June 30, 2010, respectively. Our income tax expense includes federal, state and foreign income taxes at statutory rates and the effects of various permanent differences.

Our effective tax rates for the quarters ended June 30, 2011 and 2010 were 42.6% and 39.3%, respectively. For the six months ended June 30, 2011 and June 30, 2010, our effective tax rates were 40.8% and 39.3%, respectively. Our effective tax rate is higher than the statutory U.S. tax rate in all periods primarily due to state income taxes and certain share-based compensation that is not tax deductible. In addition, the effective tax rates for the quarter and six months ended June 30, 2011 are higher than the statutory U.S. tax rate due to an increase in the fair value of contingent consideration that is not deductible for tax purposes.

During the six months ended June 30, 2011, we had no material changes to our liability for uncertain tax positions. The examination of our 2008 U.S. income tax return concluded during the quarter ended March 31, 2011 with no material adjustments. Various state income tax returns are currently under examination. At this time, we do not believe that the results of these examinations will have a material impact on our financial statements.