What is the largest portion of the federal revenue?

The largest portion of the federal revenue comes from individual income taxes. In 2008, individual income taxes made up 45 percent of the federal revenue. In 2008, individual income taxes totalled $2.5 trillion.

For more information, go to the Urban Institute and Brookings Institution Tax Policy Center website, www.taxpolicycenter.org/briefing-book/background/numbers/revenue/cfm, to view 'The Numbers: What are the federal government's sources of revenue?'