WASHINGTON — The American population is growing at its slowest pace since 1919, new government data shows, as a drop in births and an acceleration in deaths put the country closer than ever to an overall decline.
The figures, released by the Census Bureau on Thursday and analyzed by demographers, were for the 12 months that ended in July 2019, long before the coronavirus began to spread in the United States. Experts said that if one of the more dire projections of coronavirus-related deaths holds true, the country could face its first yearly drop in population, particularly if immigration continues to fall.
“If this epidemic is as significant as some think, we could have deaths exceeding births in the nation as a whole, which has never happened in the history of this country,” said Kenneth Johnson, a demographer at the University of New Hampshire, who analyzed the numbers.
Experts point to what they say is a perfect storm, in which the three forces that make up a country’s population growth — births, deaths and immigration — have all gone off-kilter.
A sharp and steady decline in the birthrate since the Great Recession means births are no longer such a powerful driver of growth. Immigration, which would typically pick up the slack, is down sharply too. And deaths are rising as baby boomers age and drug overdoses surge. Now there is the added threat of the coronavirus, which is particularly lethal for older people.
Births fell to 3.79 million in the year ending in July 2019, while deaths jumped to 2.83 million. That difference — the natural growth of the population — is now less than 1 million for the first time in decades. When combined with immigration, which fell to a net gain of 595,348 people — down by nearly half since 2016 — the United States had a population increase of just 0.48 percent.
That is the lowest rate since the last time the country was in the midst of a severe pandemic — the flu that killed hundreds of thousands of Americans between 1918 and 1919.
William Frey, chief demographer at the Brookings Institution, said the numbers put the last decade on track to be the slowest 10-year period for population growth since the government started counting in 1790.
The balance of births and deaths is critical to a country’s demographic health. If deaths start to outnumber births — and immigration does not make up the difference — society can strain under the weight of a growing retiree population with too few working-age people to support it. Deaths exceed births in several European countries, including Italy, Greece, Germany and Spain. In some, immigration keeps the populations growing.
The new census data offers details about the populations of counties and metropolitan areas. Dr. Johnson calculated that deaths now exceed births in about 46 percent of counties in the country, far more than at the start of the decade, when the pattern held in just 29 percent of counties. Now large swaths of New England, Western Pennsylvania, Central Florida and much of Appalachia glow red on his map of counties that exhibit the pattern.
Once the pattern starts, it can be hard to stop. Dr. Johnson estimated that 90 percent of the counties that experienced the imbalance in one year saw it repeated during the decade. These tend to be places with little immigration and a dwindling number of young families. Their schools tend to close because there are not enough children to fill them.
All of this has had a dramatic effect on the populations in cities and towns. Large metro areas had the steepest decline over the course of the decade, Mr. Frey found in an analysis, with the growth rate down by nearly half. Rural areas, in contrast, grew slightly by the end of the decade, though that followed several years of declines.
Places that had once been popular destinations for young people — New York, Los Angeles and Chicago — ended the decade with some of the biggest declines. New York began losing population in 2017, and last year it registered a loss of more than 60,000 people, the biggest population decline of any American city, Mr. Frey found.
The housing market collapse of 2008 and the rising prices in suburbs prompted millennials to move to big coastal cities. But that pattern reversed by mid-decade, Mr. Frey said, as millennials fled rising rents and home prices.
Places with the biggest gains for the decade were Dallas, Houston, Phoenix, Atlanta and Washington, D.C. Medium-size metro areas, like Las Vegas, have also moved up the ranks of gainers, as have Charlotte, N.C.; Seattle; and Austin, Texas.