In 2000, for instance, the top 1 percent of income earners paid 37.42 percent of all income taxes collected. In 2008, they paid 38.02 percent. That's down a bit from the peak of 2007 and reflects the recession hitting. The bottom 50 percent of filers saw their share of the income tax burden fall from 3.91 percent to 2.7 percent.
http://sayanythingblog.com/entry/bus...ng-more-taxes/
try this link for more.
It will also take you to the tax foundation website, which is very informative