From Slate today

Still, the evidence suggests that America’s wealthiest faced a significantly higher tax burden during the country’s years of midcentury prosperity. Thomas Piketty and Emmanuel Saez, for instance, find that, once corporate and estate taxes are added into the mix, the top 0.1 percent of earners paid 71.4 percent of their income to the IRS in 1960, compared to 34.7 percent in 2004. Reaching further back and using slightly different methodology, the Congressional Research Service finds that 0.1 percenters paid an average effective personal income tax rate of 55 percent in 1945, compared to around 25 percent during the late 2000s. The tax code really was more progressive back in the day—and more aggressive.

Here's the link.