Census: Aging America

 From the Census Bureau:

Today, the U.S. Census Bureau released the 2020 Census Demographic Profile and Demographic and Housing Characteristics File (DHC). These products provide the next round of data available from the 2020 Census, adding more detail to the population counts and basic demographic and housing statistics previously released for the purposes of congressional apportionment and legislative redistricting.

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• The 2020 Census shows the following about the nation’s age and sex composition: Between 2010 and 2020, median age in the U.S. grew older due to an increase in the older population.In 2020, there were 55.8 million people age 65 and over in the United States (16.8% of the total population), up 38.6% from 40.3 million in 2010. This growth primarily reflected the aging baby boom cohort.
• Centenarians grew 50% since 2010, the fastest recent census-to-census percent change for that age group

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• In 1970, after all the Baby Boomers (1946-1964) had been born, half of the population was younger than 28.1 years old. By 2020, the median age was 38.8, an increase of more than 10 years over the past five decades.In 2020, the population age 45 and over accounted for 42% of the total population, up from 27% in 1940, the census before the Baby Boom began.
• The share of the population age 65 and over more than doubled between 1940 and 2020, from less than 7% to nearly 17%.
• In 2020, there were over 73.1 million children under age 18 (22.1% of the total U.S. population), down 1.4% from 74.2 million in 2010. The biggest decline was among the under-5 age group, whose share of the population dropped by 8.9% or 1.8 million. This finding is consistent with the decline in the total number of births and the birth rate for the United States since 2015.
• Among the states in 2020:Fourteen states had a median age over 40, twice as many as in 2010. Twenty-five states had higher shares of population age 65 and older than Florida had in 2010 (17.3%), when it had the highest share of any state. In 2020, Maine had the highest share at 21.8%, followed by Florida (21.2%) and Vermont (20.6%).
• Utah and Maine were the youngest and oldest states (as they were in 2010). Nearly half of Utah’s population was under age 31 while more than half of Maine’s population was over age 45.

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The public can explore these age and sex statistics in two data visualizations:
Exploring Age Groups in the 2020 Census. This interactive map shows certain measures — percent of population, percent change from 2010, percent female and racial and ethnic diversity index and prevalence — for a variety of age groups for the nation, states, counties and census tracts. The visualization also provides ranking lists of the measures.
How Has Our Nation's Population Changed? This interactive visualization shows population pyramids and ranked age and sex measures for the total population, as well as race and Hispanic origin groups, for the nation, states, metropolitan areas, micropolitan areas and counties in 2020, 2010 and 2000.

A series of downloadable ranking tables related to each visualization is also available.

More information about age and sex is also available in the America Counts stories: An Aging U.S. Population With Fewer Children in 2020 and 2020 Census: 1 in 6 People in the United States Were 65 and Over, and two briefs: Age and Sex Composition: 2020 and The Older Population: 2020.