Our effective income tax rate was 31.1% in 2008 (23.9% in 2007 and 28.6% in 2006). The rate increased in 2008 compared to 2007, primarily due to the recognition of a valuation allowance on our deferred tax assets due to the uncertainty of realizing tax benefits related to impairments of our equity investments. In addition, the rate increased in 2008 compared to 2007, due to the reversal of previously accrued taxes of $481 million (including $50 million of accrued interest) related to settlements with the U.S. Internal Revenue Service (IRS) in the first and second quarters of 2007. Our effective income tax rate was lower in 2007 compared to 2006, primarily due to the settlements with the IRS.