The U.S. population will grow older and more diverse over the next four decades, according to new Census Bureau projections presented Thursday at a meeting of demographers.
As the U.S. median age increases, there will be a smaller ratio of workers in the labor force able to pay the payroll tax that funds Social Security payments to people of retirement age. In 15 years, the number of people over age 65 will be larger than the number of children for the first time in U.S. history, according to the presentation at a Southern Demographic Association meeting in New Orleans.
A "demographic tidal wave" is one big reason for the nation's expected aging and the eventual drop in natural population increase from births outpacing deaths. That wave is the Baby Boomers, born between the end of World War Two and around the time of the American invasion of The Beatles.
"The youngest Baby Boomers are 55 and older now, said Allison Plyer, a demographer attending the meeting. "In 10 years, they will be 65 and older, and as those folks pass away over the decades, that's a very larger section of our population reaching an age where they will likely experience mortality," Plyer said.
As the U.S. grows older, it will also become more diverse, with children leading the way. By next year, no single race group alone will make up more than half of U.S. children, the projections show.
Although non-Hispanic whites currently are a majority in the U.S., their numbers will dip below 50% of the population in 40 years, declining from 199 million next year to 179 million in 2060, the projections show.
"Immigrants do continue to fill in the ranks of working-age population and workforce as the Baby Boomers age," Plyer said. "The most likely people to replace them will be people of color, particularly Latinos who are already here and have children."
People who identify as two or more races will be the fastest-growing group in the next 40 years, with their population expanding as births outpace deaths.
Other fast-growing groups include Asians, whose growth will be driven by migration, and Hispanics, whose growth in the U.S. will be driven by natural increases, according to the projections.
The U.S. is expected to cross the 400 million-person threshold by 2058, as it adds 79 million more people in 40 years, but annual growth will slow down. The U.S. has about 326 million people today.
Population growth, currently 2.3 million people per year, is expected to slow to 1.6 million people a year by 2060.
Growth comes from immigration and from births outpacing deaths, but that natural increase will decline as the nation ages. The nation's median age is expected to go from 38 today to 43 by 2060.
Young adults are getting married and having children at older ages than their parents and grandparents, and they won't be having children in the numbers to replace the Baby Boomers, said Andrew Beveridge, a demographer at the City University of New York.
As the number of people over age 65 grows, the share of working-age adults — who pay, along with their employers, for Social Security through a payroll tax — will also decline. Next year, there are expected to be 3.5 working-age adults for every person of retirement age, but that ratio declines to 2.5 by 2060, according to the projections.
That ratio will put the U.S. more in line with Europe, though it won't be as severe as in Japan, which for years has had an aging population without the help of migration to add to the population, the demographers said.
"It's definitely a shift, but we're not going to be like Japan," Beveridge said.
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