In each state in the nation, the top 1 percent of earners saw its share of the income pie grow between 1979 and 2007, according to a new 50-state study of income inequality. The change was starkest in Wyoming, where 9 percent of income belonged to the top 1 percent in 1979. By 2007, that top slice of earners laid claim to 31 percent of all income.
It hasn’t always been the case, though. As the GIF above and graph below both show, the top 1 percent saw its share of all income shrink between 1928 and 1979. Over that half-century, the income pie was shared a little more equally. But since 1979, that trend reversed in every state, according to a new study from the Economic Policy Institute, a think tank that focuses on the needs of low- and middle-income workers.
The authors of the report borrowed the methodology of economists Emmanuel Saez and Thomas Piketty, a duo renowned for their research into income inequality. To get the income data in each state, they analyzed tax data from the Internal Revenue Service. Using that data—which includes the amount of income and the number of taxpayers in each bracket—they extrapolated how it would breakdown along a distribution. They then used state Census data and Piketty-Saez national estimates to identify how to apply that breakdown to each state.