It seems that America’s biggest nurseries are failing at their job.

Those “nurseries”—the states with the largest-growing youth populations—tend to produce the worst outcomes for kids, judged by such measures as high-school graduation, access to health insurance, and exposure to poverty. The states that produce the best outcomes for kids tend to be either stagnant or declining in their youth populations.

That means the United States is increasingly relying on the states that are most struggling—and often making the least effort—to equip their kids to succeed and ultimately build the country’s future workforce and consumers. “The fact that we have so many kids living in parts of the country where the outcomes aren’t as good … is something we are going to pay for later,” says the demographer Bill Frey, a senior fellow at the Brookings Institution’s Metropolitan Policy Program who recently analyzed the youth-population trends for all 50 states.

These conclusions are based on a comparison of Frey’s analysis with the latest Kids Count data book from the Annie E. Casey Foundation (which is among the sponsors for the series that produced this piece). The foundation ranks the condition of children in the states across 16 quantitative indicators in education, health, family, and the economy. From these individual assessments, it synthesizes a cumulative rank of well-being for children in each state.

Comparing that ranking with Frey’s analysis—which looked at changes in the 20-and-younger population for each state between 2000 and 2014—produces results that are ominous for the nation’s future economic vitality and social stability.

The 15 states that the foundation ranked as producing the best outcomes for kids are mostly clustered in New England (New Hampshire, Massachusetts, Maine, Vermont, Connecticut), the Midwest (Minnesota, Iowa, Wisconsin) and the mid-Atlantic (New Jersey, Maryland, Virginia). But in nine of the 15 highest-ranked states, the number of young people declined from 2000 through 2014, Frey found. Only in Utah and Virginia  did the number of young people increase by at least 5 percent.

The 15 states that Casey ranked as producing the worst outcomes for kids are clustered in the Sun Belt (ranging west from South Carolina, Georgia, and Florida to Texas, Nevada, and California) and the Appalachia region (West Virginia, Tennessee, Kentucky). In nine of the 15 lowest-ranked states, the number of young people increased between 2000 and 2014. The increase reached double digits in six of those states.

Overall, nearly 37 million young people—representing 45 percent of Americans under 20—now live in the 15 states at the bottom of the Casey foundation list. Just 15 million youth, representing only 19 percent of that same age cohort, live in the top 15 states. Moving forward, this discrepancy may only widen: Of the 15 states that experienced the largest percentage increases in their youth populations, nine rank in the bottom 15 and just one is in its top 15.

Several chasms separate kids’ experiences across these states. For one, the share of children in poverty is lower than the national average (which was 22 percent in 2013) on all 15 states topping the list. Meanwhile, the share of children in poverty exceeds the national average in all 15 states at the bottom, including Texas (25 percent), Arizona (26 percent), and Georgia (27 percent). Results for high-school graduation rates and access to health insurance follow similar patterns.

Another chasm that separates the highest and lowest-ranked states is diversity. Nonwhites represent a majority of kids under 20 in just two of the 15 highest-ranked states, while they account for a majority of the under-20 population in eight of the 15 lowest ranked states (including Georgia, Florida, Texas, and California), and at least two-fifths of the age cohort in four others.

The Sun Belt states seem to face the most acute challenge of putting more kids of color on track to the middle class. But that is increasingly becoming a national phenomenon. Frey’s data shows that the absolute number of white kids under 20 has declined in 46 of the 50 states since 2000. Against that backdrop, a failure to elevate the children of color, who will comprise a growing share of the workforce almost everywhere, will hurt not only the states in which they live, but also the nation’s competitive edge.

Largely for that reason, Rolf Pendall, the director of community policy at the nonpartisan Urban Institute, says the U.S. can no longer accept the historic tendency in which Washington primarily held the funding responsibility for programs affecting senior citizens while the states were charged with overseeing children’s programs. “Increasingly it’s a limited number of states, and a limited number of metro areas, that are the nurseries of the future workforce,” Pendall says. “That means it’s in the national interest to provide for maximizing the life chances of kids [in those] places. That’s … not charity. It’s investment.”

That recognition could translate into providing a national baseline of services, like access to preschool and health insurance for all kids, and a livable wage for parents. But it also means that the well-being of all Americans could be undermined if the states most responsible for nurturing the next generation don’t commit to improving the outcomes for those kids.