“BEA’s economic areas define the relevant regional markets surrounding metropolitan or micropolitan statistical areas. They consist of one or more economic nodes – metropolitan or micropolitan statistical areas that serve as regional centers of economic activity – and the surrounding counties that are economically related to the nodes.”
(click for BEA’s enlarged version)
Annual income data by area for 1979-2008 can be found through the BEA’s interactive Bearfacts map.
[Map via Bureau of Economic Analysis]