New US Census Bureau data shows that while the median household income for the United States (and 14 states within the USA) increased a bit from 2017 to 2018, "income inequality was significantly higher during the same period for the nation and nine states…. Maryland ($83,242) was among the states with the highest median household income and West Virginia ($44,097) was among the lowest."
More data and an interactive version of the map: "2018 Median Household Income in the United States" (Census.gov)