Trends in Economic Inequality: Are U.S. states growing apart?

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 across the states. The results show that states belonging to the South and West regions are growing apart, contributing significantly toward the level of total economic disparity in the country. However, in terms of per-capita real GDP, economic disparity across states is much smaller. The results emphasize the role of population dynamics in mitigating economic disparity across U. S. states.