Trends in U.S. Spatial Inequality: Concentrating Affluence and a Democratization of Poverty

We study trends in income inequality across U.S. states and counties 1960-2019 using a mix of administrative and survey data sources. Both states and counties have diverged in terms of per-capita pre-tax incomes since the late 1990s, with transfers serving to dampen this divergence. County incomes have been diverging since the late 1970s. These trends in mean income mask opposing patterns among top and bottom income quantiles. Top incomes have diverged markedly across states since the late 1970s. In contrast, bottom income quantiles and poverty rates have converged across areas in recent decades.