US State Level Income Inequality

Rising income inequality in the United States over the past quarter century is well documented. For the vast majority of states, the share of income held by the top decile experienced a prolonged period of stability after World War II, followed by a substantial increase in inequality during the 1980s and 1990s. And the most interesting fact that the rising income inequality has positive correlation with the growth of real personal per capita income.
Frank, Mark. W. 2009 "Inequality and Growth in the United States: Evidence from a New State-Level Panel of Income Inequality Measure" Economic Inquiry, Volume 47, Issue 1, Pages 55-68