To understand one of the principal forces remaking Chicago, take a walk from Wrigley Field south on Clark Street, then turn down Sheffield Avenue.

On just about every block, it seems, there’s a bar decked out with a Big Ten banner.

Northwestern. Indiana. Wisconsin. Michigan State. Maryland.

Maryland? Oh, right, it joined the Big Ten in 2014.

More Big Ten graduates live in Chicago than in any other city — according to LinkedIn, the career networking site, 338,000 of them, more than in New York (316,000), Washington, D.C. (203,000) or San Francisco (111,000).

And it isn’t just Big Ten grads flocking to Chicago. As the chart below shows, Chicago has the highest percentage of college graduates of the seven biggest cities in the United States.

They’re not just coming from Champaign-Urbana and West Lafayette, Indiana. Chicago increasingly is pulling in college grads from its own suburbs, too. Ten years ago, 38% of college graduates ages 25-34 in the Chicago metropolitan area lived in the city. Today, it’s an astonishing 46%, even though the city accounts for less than 30% of the region’s population.

The influx is transforming what once was a working-class city. In 1990, fewer than 20% of Chicagoans were college graduates. Today, that figure is approaching 40%.

You can see the changes in Chicago’s neighborhoods, too. Many have been revitalized by college graduates and not just on the North Side but also along the lakefront as far south as Woodlawn.

Not everyone is happy about that. College graduates are the driving force behind gentrification for the obvious reason that they’ve got more money than everybody else. The average Chicagoan with a bachelor’s degree makes $56,000. Those with only a high school diploma make just $26,000.

Rents, housing prices and property taxes driven up by college grads have given rise to a lot of resentment. Some people have called for drastic measures to limit the effects of gentrification, from rent control to limits on building conversions.

But whatever problems the growing number of college graduates might be causing, the real danger is that the city won’t be transformed fast enough.

To see why that’s so, I created the maps below, using data collected by the Census Bureau. They show the relationship between education and money in 2010 vs. 2017, the latest year for which numbers are available.

I categorized the city’s neighborhoods according to two metrics — the percentage of college graduates and median household income.

For the first: Either a neighborhood had at least the same percentage of college graduates as the national average, or it didn’t.

Median income was more complicated. The Pew Research Center, a nonpartisan Washington think tank, divides households into three categories: upper income, middle income and low income. Upper income means a neighborhood’s median household income is at least twice the regional average. Low income means median income is less than two-thirds the regional average. Middle income is everything in between.

I used Pew’s approach, taking the Cook County median as my benchmark. The maps show the result.

Bottom line: A lot of the city is doing well, and that’s due largely to college graduates.

And a lot of it isn’t. The question is whether the forces pushing Chicago up can overcome those pushing it down.

The maps have six colors. Here’s what they mean:

Black — upper income, above-average college

Chicago doesn’t have a lot of truly wealthy communities, but it has some — and the number is increasing. In 2010, there were 17 upper income neighborhoods. By 2017, that figure had more than doubled.

Blue — above-average income, above-average college

Blue indicates upper middle class. In 1980, only a few neighborhoods in Chicago fell into that category. Today, many do. And the number has grown noticeably since 2010. You can thank college graduates for that.

Red — below-average income, above-average college

An interesting category, it shows that, while a college education tends to be a prerequisite for making big money, it’s not a guarantee.

Sometimes, red just signals that a neighborhood is gentrifying. In some parts of the city, the number of college grads is growing, and so are their earnings. Communities like that will most likely be affluent someday.

But other neighborhoods have stayed red for a long time — Edgewater and Rogers Park on the Far North Side among them.

These neighborhoods tend to be stable. The college graduates who live in them presumably could have gone elsewhere but chose to stay, and their neighborhoods are the better for it.

Green — above-average income, below-average college

Proof that you can still make a decent buck without a college degree if you’re in the right line of work, these neighborhoods tend to be on the edge of the city, where a lot of Chicago police officers and firefighters live.

Orange — below-average income, below-average college

These are Chicago’s working-class neighborhoods. They’re not poor — median income is above the poverty line. But they skate close to the edge financially.

Yellow — low income, below-average college

These neighborhoods are poor.

At a glance, the 2010 and 2017 maps seem similar. But close inspection reveals critical differences.

Neighborhoods with a lot of college graduates, shown in black, blue and red, gradually are becoming more numerous — even the ones whose residents aren’t making a lot of money.

Neighborhoods without a lot of college graduates, shown in green, orange and yellow, are declining — numerically for the orange and green, economically in the case of yellow.

The biggest loss is in working-class communities, particularly on the West Side and South Side. A number of green districts have turned orange, and a lot of orange ones have turned yellow. These neighborhoods once were working class. Increasingly, they’re becoming poor.

Gentrification isn’t the problem. Fewer than 30 working-class neighborhoods gained enough wealth or enough college graduates to push them into a snootier category.

More than twice as many working-class neighborhoods slid into poverty. The continuing departure of middle-class black people — including a fair number of college graduates — is surely the key factor in the declining fortunes of communities on the West Side and South Side.

Chicago is in the grip of forces pulling in opposite directions. Gentrification caused by the growing number of college graduates is pushing parts of the city up. Increasing poverty due to the exodus of middle-class black people is pushing other ones down.

If we decide the more important problem to solve is gentrification and take steps that stifle investment and make parts of the city less attractive to the well-educated, we’ll be slitting our own throats.

This is part of the series City at the Crossroads by journalist Ed Zotti, who takes an in-depth look at trends affecting Chicago and critical choices the city faces.

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