balance at december 31 $ 99 $ 110 the amount of unrecognized tax benefits was $ 99 million and $ 110 million as of december 31 , 2008 and 2007 , respectively . if recognized , $ 89 million and $ 88 million would impact the effective rate as of december 31 , 2008 and 2007 , respectively . the company recognizes accrued interest and penalties related to unrecognized tax benefits in income tax expense