(CNN) — The US population has gotten older in the past two decades, with more aging adults and fewer children under the age of 5, new Census Bureau data reveals.

From 2000 to 2020, baby boomers and millennials – the largest age groups in the United States in 2020 – continued to age, and at the same time, from 2010 to 2020, smaller cohorts of children were born, according to data from the 2020 Census Demographic and Housing Characteristics, released Thursday.

Overall, the new data reveals that the median age of the US population rose from 35.2 in 2000 and 37.2 in 2010 to 38.8 in 2020. By state, Maine had the oldest median age, 45.1, in 2020, and Utah had the youngest, 31.3.

Additionally, the population of adults 65 and older grew nearly five times faster than the total US population in the past century, from 1920 to 2020, according to the Census data. That age group represented 16.8% of the total US population in 2020.

There is growing concern about what the public health needs of an aging population will look like.

“The US 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, while the share of the US population that is 65 and older increased, the United States remains “relatively young” compared with many of 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% of the population in 2020, followed by Italy at 22.6% and Greece at 22.4%.

“The US grew older from both a decrease in the number of children and an increase in the older population between 2010 and 2020,” Mary Leisenring, the Census Academy program lead, said in a YouTube video distributed by the US Census Bureau on Thursday.

The recent Census data also showed that “the nation’s multiracial population was the youngest of any race group in 2020,” Leisenring said, referring to the population of people who identify as two or more races. “There were around 9 million people who identified as multiracial in 2010, and that group had a median age of only 19.9. But, by selecting the 2020 button, we see the population increased to almost 34 million with a median age of 29.5.”

The-CNN-Wire
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