U.S. — The U.S. Census Bureau announced in July 2025 that the nation's median age reached 39.4, as detailed in its Vintage 2025 population estimates. This represents an increase from 38.6 five years prior.

The estimates showed that the number of people older than 65 in the U.S. increased by 16.2% between 2020 and 2025. During the same period, the number of individuals aged 25 to 44 rose by 5.9%, and those aged 18 to 24 increased by 2.1%. Conversely, the population under 18 decreased by 2.4%, and the population aged 45 to 64 declined by 3.2%.

The South was the only U.S. region to experience population growth across all five age cohorts between April 2020 and July 2025. The overall population of the South grew by 6% during this timeframe, contributing to the total U.S. population growth of 3.1%. The under-18 population in the South expanded by 1.1%.

Other regions experienced declines in certain age groups. In the Northeast, the under-18 population decreased by 4.1%, and the population aged 45 to 64 saw a 7.1% reduction. The Gen X generation includes those born roughly between 1965 and 1980.

The Midwest recorded a 3.9% decrease in its child population and a 6.2% decrease in its midlife cohort population. The West experienced a 5.7% decrease in its child population, and its Gen X-aged population fell by 2.7%. The Gen X-aged population in the South, however, saw an increase of approximately 19,000 people, or 0.1%.

Lauren Bowers, chief of the Census Bureau's Population Estimates branch, noted specific factors influencing these shifts. "Regional age patterns are changing for a few key reasons," Bowers said. She added, "The continued transition of baby boomers into retirement age, compounded by local migration and fertility patterns, is shifting the demographic makeup of the country."

The baby boomer generation, which peaked at 79 million people in the 1990s, currently comprises approximately 76 million people, and the last baby boomer was born in 1964. The millennial generation comprises approximately 72 million people, while the Gen X generation includes approximately 65 million people. Baby boomers currently own one third of the nation's housing stock.