But will raising top tax rates significantly lower economic growth? In the postwar U.S., higher top tax rates tend to go with higher economic growth—not lower. Indeed, according to the U.S. Department of Commerce’s Bureau of Economic Analysis, GDP annual growth per capita (to adjust for population growth) averaged 1.68% between 1980 and 2010 when top tax rates were relatively low, while growth averaged 2.23% between 1950 and 1980 when top tax rates were at or above 70%.

Neither does international evidence support a case for lower growth from higher top taxes. There is no clear correlation between economic growth since the 1970s and top tax-rate cuts across Organization for Economic Cooperation and Development countries.

For example, from 1970 to 2010, real GDP annual growth per capita averaged 1.8% and 2.03% in the U.S. and the U.K., both of which dramatically lowered their top tax rates during that period, while it averaged 1.72% and 1.89% in France and Germany, which kept high top tax rates during the period. While in no way does this prove that higher top tax rates actually encourage growth, there is not good evidence from the aggregate data supporting the view that higher rates slow growth.