Using quarterly real GDP data from 2005 to 2019 for all U. S. states from the Bureau of Economic Analysis, we construct an economic inequality measure which is additively decomposable into within and between-region inequality. We find increases in economic disparity in terms of total real GDP...

Understanding within and between group inequality is fundamental in understanding the evolution of income inequality in any country. Using a century of data for France, and the Theil measure of income inequality, which is decomposable, we show that income inequality within the bottom 90\%...