By John Hood

RALEIGH — In 1940, some 3.6 million people lived in North Carolina, ranking the state 11th in the nation in population and first in the Southeast.

Across the South as a whole, only Texas (6.4 million) was more populous.

If present trends continue, by 2040 North Carolina will have a population of about 12.7 million, ranking us seventh in the nation but only fourth in the South, after Texas (40 million), Florida (28.9 million), and, just barely, Georgia (12.8 million). By that time, more people will live in North Carolina than in Illinois or Ohio.

Surprised? Let’s see if I can surprise you again. Even as North Carolina reaches that milestone, our population growth rate will be declining. According to projections from the University of Virginia’s Demographics Research Group, N.C.’s population will have risen 10.8 percent from 2010 to 2020, 10.5 percent from 2020 to 2030, and 8.4 percent from 2030 to 2040.

These increases will still outpace the average national rate, which is also projected to decline. But keep in mind that North Carolina’s growth rates have historically been far higher — 12.7 percent in the 1980s, 21.4 percent in the 1990s, and 18.5 percent in the 2000s. Indeed, if the 2020-2040 projections prove accurate, North Carolina will grow at our slowest rate since the tumultuous 1860s (7.9 percent).

Part of the explanation is that Americans as a whole are less likely than their predecessors to move across state lines. This is another trend that many may find surprising, especially if they live in rapidly growing communities full of new arrivals. The other, larger story is simply that fertility rates are declining and immigrants from other countries are not expected to make up the difference.

Although the growth rate may decline on a percentage basis, our state is still poised to add lots of new residents — more than two million more North Carolinians by 2040. Our economies, communities, and politics will change accordingly. Some of these effects are (sort of) predictable. Others may well present us with still more surprises.

We assume based on recent experience, for example, that these new North Carolinians will live disproportionately in our largest cities.

They probably will live disproportionately in metropolitan areas, but I wouldn’t be too sure where in that rather broad swath of North Carolina they will end up working and raising their families. Relative costs, technological change, and consumer preferences fluctuate. Perhaps our largest cities will get much denser. But perhaps young natives and newcomers will prefer new centers of employment, residence, and commerce on the fringes of today’s urban cores.

In the past, policymakers also assumed that population growth meant lots more children in schools and colleges, requiring massive capital expenditures to keep up with the demand for classroom space. Yet North Carolina’s school-aged population isn’t growing as rapidly as policymakers expected just a few years ago, and a higher share of those young people get their educational services in new ways — in home schools or in flexible arrangements that combine school buildings, satellite campuses, libraries, their homes, and other homes.

Even as North Carolina grows more populous, it will grow older. A lot more North Carolinians will be retired. Again, don’t make hasty assumptions. We’ll have more retirees and they’ll live longer, many into the 80s and 90s, but that doesn’t necessarily suggest our governments, households, and provider networks will collapse under the strain of caring for infirm parents and grandparents. Tomorrow’s retirees will be far healthier than yesterday’s retirees were, on average, and as the American Enterprise Institute’s Andrew Biggs pointed out in recent congressional testimony, they’ll be better prepared financially than any previous generation of American retirees has been.

Back in 1940, the second-largest city in North Carolina wasn’t Raleigh. It was Winston-Salem. Durham, Greensboro, and Asheville were also more populous than the capital city at that time. Some statistician probably predicted that Raleigh would surge, but I’m sure it came as a surprise to many North Carolinians, anyway.

John Hood is chairman of the John Locke Foundation.