As home prices soared in the first years of the 21st century, several of Chicago’s most desirable suburbs saw their African American population decrease, according to new data from the Metropolitan Planning Council. At the same time, the African American population boomed in some of the outer-ring suburbs, where inexpensive subdivision houses were built in large numbers between 2000 and 2010.

“We’re seeing some large shifts in population that seem to be connected to housing choices [and] housing prices,” says Joanna Trotter, the community development director for the Metropolitan Planning Council. “Some communities are not keeping a lot of lower-cost options, so people are going where it’s more affordable.”

The three towns that lost the largest proportion of their black populations were, in order from the largest loss, Geneva, Glencoe, and Glenview. As shown in the chart below, each of those towns lost more than 30 percent of their African American population between 2000 and 2010.

In the years leading up to the real-estate bust, each of those towns saw their home prices rise by 48 percent or more. Lake Forest, which saw its home prices rise by 64 percent, lost 24 percent of its African American population during the decade. North Chicago, which lost 25 percent of its African American population during the decade, was the only nonaffluent town among the top five. (Some other towns in the Chicago area lost greater percentages of their African American population than these suburbs, but I have excluded them from the list because their losses were ten or fewer people, and each person lost had an outsize effect on the percentage.)

During the same decade, African Americans poured into five outer-ring suburbs where many new houses were going up. Yorkville, which had about a dozen black residents in 2000, and Plainfield, which had about 50, saw their African American population increase by more than 2,000 percent. The African American population increased by more than 1,000 percent in Huntley and Monee, and by 647 percent in Round Lake.

The task for towns that have seen an influx of African American families, Trotter says, is ensuring “that there is outreach to these new populations, that [you] are bringing them into the civic and cultural opportunities that are in your town so they feel that their population is represented.” She adds that her department hasn’t yet crunched the numbers for suburban changes in Hispanic or Asian populations.

The chart below shows the five towns that experienced the greatest percentage loss of their African American population between 2000 and 2010, as well as the five towns with the greatest percentage increase. (This online chart provides the data for all towns in Illinois, and this online map shows the general trend in African American movement in Chicago-area suburbs.) I have also listed the average sale price for houses in most of those towns as reported in Chicago’s annual October real-estate chart. I have included information for the years 2000, 2007 (when prices peaked), and 2010 (when prices showed the result of the housing-market bust). Three of the towns with increased populations don’t appear on Chicago’s charts, so I don’t have price information for them; sale prices there are indicated by N/A (no answer).