The Chicago Metropolitan Agency for Planning has a new overview of broad population trends in Cook and the collar counties, and within it is a bird's-eye view of race in the metropolitan area, showing how it's evolved in the past decade and a half, and where it's going—with reason for concern.

Take central Cook County. Here's what it looked like in 2000 (blue dots equal 10 white residents, green dots equal 10 black residents, orange dots equal 10 Hispanic residents, red dots equal 10 Asian residents), compared to 2010-2014 American Community Survey data:

First, there's a much greater density of Hispanic residents, and a lower density of black residents—particularly noticeable on the South Side of Chicago. Those are pretty well-known and much-discussed trends.

Related: Why Is Cook County Losing Population? It's Complicated

But there's also a greater number of Asian-Americans in the county, more dispersed throughout. "Nationwide we're seeing more and more migrants to the U.S. from Asia," says Elizabeth Schuh, principal policy analyst for CMAP. "The breakdown in our region is a little bit different. It tends to be more residents from Southeast Asia and India."

Regionwide, the percentage of Hispanics and Asian-Americans have both basically doubled. The Hispanic population has grown from about 1,410,000 in 2010 to almost 1,880,000 in 2010-2014; the Asian population has grown from about 242,000 in 1990, to 378,000 in 2000, to almost 551,000 in 2010-2014.

Meanwhile the percentage of black and white residents has shrunk, especially the percentage of white residents. The Hispanic population is now bigger than the black population in the region, by about 430,000 people.

Interestingly, the significant increase in diversity, by the broadest measure, has come outside of Chicago. The percentage of white residents in Chicago is practically unchanged from 2000 to 2010-14: 32 percent to 31 percent. It's in the surrounding area that it's changed.

Immigration has staved off what would have otherwise been dramatic population losses, and immigration from Asia has been especially important as Mexican immigration has slowed down.

It's a measure of how critical immigration is to the region—and potentially a warning about policies that would slow it down.

"The Chicago region, like many big, older, established regions—you see this in LA and New York—tends to grow partly because people have growing families, and then from international immigration, and less so domestically," Schuh says. But international immigration has slowed down considerably since the recession, growing 61 percent from 1990-2000 and just 14 percent since. Chicagoland's net international migration has been lower than that of its major peers—New York, Boston, Philadelphia, and Los Angeles—since 2011, and well below all of those except Philadelphia.

"That's part of the reason that the Chicago region is not really growing," Schuh says. "Any policies that would further slow that down could potentially increase [the decline]—we're already seeing a small population decline in the region, because that's one of our major sources of growth."

Schuh sees a lack of economic opportunity behind the region's population loss. The black unemployment rate is 18.5 percent, compared to 8.4 percent for Hispanics, 6.4 percent for whites, and 5.8 percent for Asians. The median income for black residents in the region is just $37,000, $11,000 less than that of Hispanics, $40,000 less than for whites, and $43,000 less than Asians, despite a percentage with at least some college education close to the regional average (57 percent versus 63 percent).

"There's a growing body of research that shows that that kind of economic stratification can have negative impacts on a region's ability to grow," Schuh says. "When we look at minority and low-income children in the Chicago region, we're near the bottom as far as economic mobility, and that's measured in terms of a child's ability to earn more than their parents. When you look at overall mobility, and start to step away from specific population groups, we're a little bit more at the bottom of the middle."

The Chicago region isn't alone in its challenges. Its median household income has declined since 1990 by 9.5 percent (almost $70,000 to just over $63,000 in 2014 dollars), but it's declined nine percent in Philadelphia, 8.6 percent in New York City, and 13.7 percent in Los Angeles. Its unemployment rate was 0.5 points higher than New York and Philadelphia, but 0.4 points lower than Los Angeles.

But other metros are farther along towards addressing issues of economic inequality through regional coordination.

"Most of the direct action that you've seen on this has happened within the last decade. There are a few that really stand out—the Twin Cities have worked actively to convene a broad spectrum of regional stakeholders on issues of equity. They take a very social-justice-oriented framing, so they're looking across a variety of issues, including job training and housing," Schuh says (I've written about Twin Cities regional coordination before and how it seems to be working).

She also cites the Denver region: "They're really thinking about how and where they place transportation investment in order to promote better outcomes and access to employment for residents in areas that might have been historically disinvested, and because of that have longer commutes and less access to employment," Schuh says.

In Chicagoland, fighting inequality will likely require significant regional coordination. The population is aging, particularly in the northwest Cook County suburbs and collar counties. Population decline used to be strongest in Cook and DuPage counties, "which are larger, older, more established counties," Schuh says, with people moving further away from the urban center but staying in the region. Now, residents appear to be leaving the area entirely—suggesting regional issues (like low economic mobility and high uneployment) are in play.