From 1930 to 2010, tax-revenue collection in the United States has never topped 20.9 percent, averaging 16.5 percent of GDP over 80 years. This despite the drastic historical fluctuation in tax rates on the wealthiest Americans.
This is called Hauser’s Law, after Standford University professor Kurt Hauser.
Chart originally seen here.
Hauser’s article in the WSJ laying out his plan here. A lot of interesting economic info in the Hauser piece, including arguments for why conservatives are correct regarding the Bush tax cuts and the Obama administration is (surprise!) prescription pills online wrong.