This is a plot of the Dissimilarity Index between African Americans and whites in states and major cities in the United States. The Dissimilarity Index is a common measure of segregation and I use it often in my research. It measures the proportion of one group that would have to move across areal units within a geography to achieve balance between groups across areal units. So, looking at the plot here, in Gary, Indiana, the most segregated major city in the United States with a Dissimilarity Index of almost .9, for African Americans and whites to achieve racial balance, almost 90% of African Americans would have to move to new Census Tracts. Data is from the 2000 Census

In this plot, the y-axis is population in units of 100,000, the x-axis is the Dissimilarity Index, the blue dots are cities (Metropolitan Statistical Areas) and the orange bars are states.

Click here to see the plot: Segregation in the United States.