Tax Data. This may be a dead horse at this point, but here are some links to US tax data. Despite what some may say, the evidence does not suggest that the rich are not paying their fair share. By the way, tax rate DECREASES under President Bush did INCREASE revenue. I expect that the opposite will happen in the future under the higher rates.
Distribution of Household Income and Federal Income Taxes, 2008 and 2009.
Federal Tax Revenues 2003 to 2006.
Social Security Tax Annual Report 2012 (Yes, it is a tax and yes you're screwed but we'll keep pretending we're not).
Pick your IRS tax stat. They are all here.