Segregation is becoming regionalized. What does this mean for the future of American politics?

In the last 30 years, segregation has changed dramatically; this map (scroll down) shows how. By comparing the proprotion of white Americans to non-white Americans in census Blockgroups to the same proportion in counties, we can create an index of segregation—lower (or blue) is less segregated, and higher (or orange) is more segregated. You can filter by level of urbanization (1 is very urban, 9 is very rural). This map also allows you to isolate counties where Trump won during the primaries. Have fun, and drop me a line to tell me how you're using it.