FOR GENERATIONS, demographers considered America a standout. Lots of immigration and relatively high fertility rates increased its population faster—and kept it more youthful—than its rich-country peers. Americans within their borders were also exceptionally mobile. Over many generations they proved much readier than Europeans, for example, to flit between cities (or states) in search of a new job or lifestyle. That dynamism helped to produce a flexible labour force and lively economy.
Now the exception is waning. Several big states have lost their demographic oomph. In mid-December the US Census published new population estimates (to be used for comparison when official census data are released in 2021). For those keen on growth, they offer mostly grim reading. California’s population has stalled and may, for the first time, be declining. Illinois, which has shed over 250,000 residents in a decade, has shrunk for seven successive years. In the year to July, thus counting in little pandemic effect, New York endured more shrinkage than any state: it lost 126,000, or 0.65%, of its people.
Some states, mostly in the South, are growing fast, but not enough to lift the national rate. Overall, America’s population is barely inching up by historical standards. In the year to July it grew by 0.35% (or 1.2m) to 329m. No year since 1900 has seen such a miserly gain, though the year to next July could be slower still. Even in the dark days after the first world war, as the Spanish flu raged, growth was faster. William Frey of the Brookings Institution calculates expansion in the decade to July 2020 at just 6.6%. If his sums are right, that is the lowest decadal gain since 1790 (see chart).
Evidence has also piled up to show Americans becoming much less mobile. Mr Frey notes a smaller share of them moved house in the year to March than at any time since reliable figures were first gathered in 1947. Just 9.3% of the population moved, barely half the figure in the 1980s, part of a steady decline over decades. Many factors contribute to that, including the high cost of housing that makes it difficult for younger Americans to move.
Kyle Mangum of the Federal Reserve in Philadelphia published a paper early in 2020 analysing why people move less frequently than their parents did, saying many factors—especially the absence of new, fast-growing cities and more similarity between various labour markets—mean that “this nation of pioneers has parked its wagons”. He also notes how technology, such as air-conditioning, previously did much to open up territory for settlement. More recent technology, notably the internet, may instead have made it less necessary to move to find work.
Various changes reinforce each other. Less immigration, for example, has several effects. The just-concluding decade will see the smallest expansion of the foreign-born population in any decade since the 1970s. Far fewer immigrants are flowing to big cities such as Los Angeles, New York and Chicago, helping to explain why they are not growing. Lower immigration hits domestic mobility, because recent immigrants are among the readiest to move for work. It may also bring down fertility rates. The average American woman is now expected to have 1.7 children in her lifetime, the lowest level in decades. That’s below France’s rate (at 1.9), on par with Britain’s, and only slightly ahead of Canada’s (1.5).
The result is more demographic stagnation. Mr Mangum sees a long-term reversion to the mean as America becomes less of an exception among rich countries. More recent influences accentuate that. The policies of Donald Trump sharply cut inflows of migrants. Joe Biden’s administration will reverse some of these but probably not all, or at least not quickly.
The pandemic has its own effects. Two academics at UC Berkeley, Joshua Goldstein and Ronald Lee, suggest deaths from covid-19, which may exceed 500,000 by April, will cut average life expectancy by more than one year. The pandemic and the economic slump are also causing a baby bust. Two researchers, Melissa Kearney at University of Maryland and Phillip Levine at Wellesley College, estimate there will be 300,000 fewer births than otherwise expected in 2021 (there were 3.7m in 2019).
Post-pandemic, some of this could be reversed. Those putting off having children may cause a brief baby boom in 2022 or 2023. Eventual reopening of borders should see immigration tick up again. Even so, slower population growth will “continue in the coming years” says Joseph Chamie, a demographer in Oregon, because America “is looking more and more like Europe, with lower fertility, more measured levels of migration”.
Does that matter? For individual states having fewer people undoubtedly hurts. Several Midwestern and north-eastern states, for example, will lose political clout as congressional and electoral-college seats go in reapportionment in 2021. It also matters for state finances if there are fewer taxpayers to pay for public services.
But for the country as a whole Mr Chamie doubts that bigger is always better. He rejects “a pro-growth dogma”, in which it is assumed that having more consumers, workers and taxpayers makes sense. He wants a debate on what is desirable, noting the environmental costs of a bigger population. The US Census set out scenarios for the forecast population in 2060. Were the country to return to being an exceptional place, open to high levels of immigration, its population could reach 447m. As a more normal rich country, less welcoming to immigrants, it could shrink to 320m. ■
This article appeared in the United States section of the print edition under the headline “The great slowdown”