The U.S. population has gotten older in the past two decades, with adults 65 or older growing by more than a third from 2010 to 2020, while the share of children under the age of 5 declined, according to Census Bureau data released May 25.
From 2000 to 2020, the median age continued to rise, while from 2010 to 2020, smaller cohorts of children were born, according to data from the 2020 Census Demographic and Housing Characteristics.
Combined, the median age in the United States has risen from 37.2 to 38.8 over the decade. By state, Maine had the oldest median age, 45.1, in 2020, and Utah had the youngest, 31.3.
The declining percentage of children comes from women delaying having babies to focus on education and careers, according to experts, who noted that birth rates never recovered following the Great Recession of 2007–2009.
“In the short run, the crisis of work-family balance, the lack of affordable child care, stresses associated with health care, housing, and employment stability, all put a damper on birth rates by increasing uncertainty and making it harder to decide to have and raise children,” said Philip Cohen, a sociologist at the University of Maryland.
Additionally, the population of adults 65 and older grew nearly five times faster than the total U.S. population in the past century, from 1920 to 2020, according to the 2020 Census. That age group represented 16.8 percent of the 331 million U.S. population in 2020.
The number of workers sharing the cost of supporting Social Security beneficiaries will soon drop unless future employment patterns change dramatically. The latest Social Security Administration projections indicate that there will be 2.1 workers per Social Security beneficiary in 2040, down from 3.7 in 1970.
The Census Bureau calculates a dependency ratio, defined as the number of children plus the number of seniors per 100 working-age people. While the dependency ratio decreased for children from 2010 to 2020, it increased for seniors by 6.8 people.
At the top end of the age spectrum, the number of people over 100 increased by half, from more than 53,000 people to more than 80,000.
“The U.S. population is indeed getting older and we are unprepared to handle their growing needs for health, habilitative and rehabilitative care in community settings,” Dr. Georges Benjamin, executive director of the American Public Health Association, said in an email Thursday. “This demographic shift is uneven and requires sound planning if we are going to ensure the capacity to protect and ensure public health as our demographics change.”
Globally, the United States remains “relatively young” compared with many of its peer high-income nations, according to the Census Bureau. Peer nations with the largest share of adults 65 and older are Japan, where that age group represented 28.5 percent of the population in 2020, followed by Italy at 22.6 percent and Greece at 22.4 percent.