[I]n 1960, blacks made up less than 1 percent of the population in 56 percent of city census tracts (tracts are census-defined units with about 5,000 inhabitants). Almost one in five tracts had no black Americans. By 1990, only about 7 percent of city tracts were 100 percent white.
As the figure shows, as of 1970, almost 80 percent of either whites or blacks would have had to move neighborhoods in order to achieve an even distribution of whites and blacks within the average metropolitan area. By 1990, that dissimilarity measure had dropped to 66 percent; it is 54 percent today. We are very far from living in a perfectly integrated society, but our nation is far more integrated than it was 40 years ago.
The progress over the last decade has been particularly dramatic. Every one of the 10 largest metropolitan areas experienced drops in both dissimilarity and isolation of 3.6 points or more. The isolation index is below 45 percent in every one of those 10 largest areas, except for Chicago. Long among the most segregated places in America, the Windy City has experienced a particularly dramatic decline in segregation since 2000.
Read the whole thing.