U.S. federal taxes have become more progressive since 1979, largely due to more generous tax credits for lower income individuals. Though top statutory rates fell substantially, this affected few taxpayers and was offset by decreased use of tax shelters, such that high-income average tax rates have been relatively stable. Redistribution, which accounts for both taxes and transfers, has also increased according to Congressional Budget Office data. Measures of progressivity and redistribution, however, capture different aspects of policy. Over the longer run, earlier decreases suggest a U-shaped tax progressivity curve since WWII, with the minimum occurring in 1986.