America’s demography is looking European

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...