America’s transition from an agricultural to an industrial economy resulted in a spatial shift in population, from rural to urban. As the economy continues to adapt from industrial to service- and knowledge-based sectors, we’re witnessing another population change—this time, in the country’s former industrial heartland. Residents of Rust Belt states are migrating to larger cities that have emerged as centers of success in the modern economy. But the Rust Belt’s urban resurgence disguises the reality that regional cities remain weak magnets for new residents on a national basis.

The Midwest and the northeastern Frost Belt are home to numerous stagnant and shrinking cities such as Flint, Michigan; Youngstown, Ohio; Rockford, Illinois; Muncie, Indiana; and Erie, Pennsylvania. But other cities within those states are booming. Metro hubs like Columbus, Kansas City, Des Moines, Grand Rapids, Madison, and Minneapolis-St. Paul are growing and thriving. These large cities are complemented by smaller success stories, including Iowa City; Lafayette, Indiana; and Traverse City, Michigan.

Some Rust Belt cities are growing faster than the nation as a whole and, at times, approaching Sunbelt rates. Between 2010 and 2017, the U.S. population grew by 5.3 percent. During that period, Des Moines exploded by 12.9 percent and Columbus by more than 9 percent. Grand Rapids, Indianapolis, Madison, and Minneapolis each grew by more than 7 percent. Such vibrancy is impressive, but a look behind the numbers shows that a qualitative difference exists between Rust Belt cities and Sunbelt boomtowns. While Sunbelt cities draw migrants from around the country, including large numbers from California and New York, larger Rust Belt cities draw overwhelmingly from their home states and adjacent areas.

An analysis of county-to-county migration data, based on IRS tax returns, shows that metro Columbus attracted nearly 67,000 people from other parts of Ohio between 2000 and 2016, while losing 28,000 people to the rest of the country. During the same period, Indianapolis drew 74,000 people statewide but only broke even at a national level. Des Moines, meantime, attracted 40,000 Iowa residents, but lost over 1,000 nationwide. The Twin Cities pulled 20,000 people from Minnesota and Wisconsin, but lost 44,000 to other states.

Retiree migration accounts for a good portion of these numbers. Rust Belt cities are losing large numbers of residents to Florida and Arizona, perhaps an unstoppable trend. Yet Nashville, Charlotte, and Austin buck the trend—they draw people from Florida. California is even more perplexing: despite its middle-class exodus, the state is drawing net new residents from the Twin Cities, Columbus, and Indianapolis.

In short, population growth in the old industrial heartland appears to consolidate within a limited number of successful metro regions, while the rest of the Rust Belt shows weak to negative demographic trends. Since 2010, Iowa and Ohio—outside Des Moines and Columbus—have lost population. Indianapolis accounted for 77 percent of Indiana’s population growth.

The population shift into successful major cities—or at least a state’s largest city—makes sense considering economic trends. Metro regions of more than 1 million people have added jobs faster than other areas since the recession. These larger cities have bigger agglomerations of college-educated talent, sizable labor markets for today’s dual-career families, connectivity to the global economy through major airports, and the urban amenities attractive to knowledge-based workers and firms.

The shift may be difficult to stop, creating challenges for smaller, stagnant places—but also masking some long-term challenges for the growing cities. As the populations of Rust Belt states decline, especially among younger cohorts, the inbound flow of people also decreases. A demographic boost driven by in-state migrants won’t last forever. Also, the superior national draw of Sunbelt boomtowns creates an advantage with marquee employers. Amazon’s plan to locate 5,000 jobs in Nashville is a good example, as is Apple’s large expansion in Austin. These companies know that even if the talent they need isn’t located in these cities, they can recruit from anywhere.

By contrast, even the most attractive Midwest cities have a tough time convincing people from the coast to relocate. Cities like Minneapolis and Grand Rapids have enjoyed growth, but to sustain it, they will need to attract migrants on a nationwide basis—in fact, their economic future depends on it.

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