If you had to summarize the demographic changes in the Chicago metro area over the last 30 years in a single statistic, you could do worse than “suburban residents used to be more likely to have a college degree, but now city residents are more likely to.” From the Chicago Federal Reserve:

Of course, though these changes are taking place at a regional scale, their effects are especially visible because they have been concentrated—that is, the additional 20 percentage points’ worth of college-degree-holders living in the city have not spread themselves around, but have segregated in a growing but modest slice of the city, running roughly from the South Loop to Andersonville, and west to Logan Square. These neighborhoods have seen massive demographic and economic change in the last two or three generations, largely because of a massive influx of college-degree-holding residents.

Something I hear a lot of people talk about is where these people come from. Are they suburbanites? Moving in from Big 10 schools or Portland or DC?

Happily, the Census can tell us where people with certain educational attainments were born! So I made a series of maps about it.

First up: College-degree-holders who were born in Illinois. (Unfortunately, Census data won’t let me get more specific than that—so these are people who could have been born in the city of Chicago, the suburbs, or even downstate.)

Importantly, these maps show the percentage of all residents who are both college graduates and born in Illinois. In other words, in the tracts colored darkest purple, more than half of all residents both have a four-year college degree and were born in Illinois.

In this map, the North Side’s “zone of affluence”—that belt stretching from downtown several miles up the lakefront, up the Blue Line, and west to about Ashland—is clearly visible. But it’s highlighted at a similar or even lesser intensity than much of the northern, western, and southwestern suburbs—as well as other city neighborhoods like Edison Park on the Northwest Side, or Beverly and Morgan Park on the Southwest Side.

What about people born in the U.S. but outside Illinois?

This map looks much, much more like the “zone of affluence” that I usually think of. An intense, tightly drawn oval from downtown onto the North Side; Hyde Park; the North Shore suburbs; Oak Park; and the suburbs along the BNSF Metra line from Hinsdale to Naperville.

But the city’s North Side zone really stands out. In places like Lincoln Park, Lakeview, and Wicker Park, 30-50% of all residents are college graduates who were born in the US outside Illinois.

It’s also clear that US-born, non-Illinoisan college graduates spread out across the city and metropolitan area much less than Illinois-born college graduates. That makes sense—”people born in Illinois” includes people who grew up in every neighborhood in the Chicago area, and you would expect many of them to stay near where they grew up. Meanwhile, people moving from other parts of the city are likely to know less about the region, and follow recommendations about where to live from their social circles, who are also likely to be from outside the region, leading to clusters. Maria Krysan’s and Kyle Crowder’s work on the way imperfect information and “choice sets” shape patterns of segregation seem relevant here.

Finally, what about foreign-born residents with college degrees? We’d expect them to cluster as well—but do they do it in the same places?

In short: Not really! In fact, the North Side zone of affluence is almost *totally gone*. There is a central city cluster, but it runs from the Loop to the South Loop and to northern Bronzeville, with another spike in Hyde Park, and another one on the West Side near the Medical District and UIC.

But there are also many suburban clusters—clusters that are not the same as either the Illinois-born or US-born clusters. The northern inland suburbs, like Skokie or Des Plaines, show up strongly; many of the western suburbs that are strongest in the other categories, like Hinsdale or Glen Ellyn, are barely visible, though Naperville is clearly a hot spot.