Just consider one fact: 39.4 the age of the average American. That’s the median age as of July 2025, up from 38.6 just five years ago. Half the country is now on the far side of 40. And buried inside the Census Bureau’s freshly released Vintage 2025 population estimates is a map of how America got here.

The data, released Thursday, tells a story about four generations and one fundamental imbalance: a country whose dominant demographic cohort is exiting productive economic life while retaining nearly all of its productive economic assets — and where every generation in its wake is either too small, too dispersed, or too financially constrained to fill the void.

America has an economic boomer hangover — the data is plain to see.

The pig in the python

It’s well known that baby boomers dominate most of the traditional statistics of economic empowerment. The generation owns one third of the nation’s housing stock and are responsible for most homebuying activity. They remain largely in control of the country’s political machine, despite the cohort’s youngest now having aged well into their 60s. The sheer size of the demographic and its staying power has also reshaped labor markets—possibly for the foreseeable future, by distorting the need for workers junior to them.

But the Census data make it overwhelmingly clear: In every region of the U.S., boomers have become more entrenched over the past few years while most other demographic groups have struggled to grow. And spare a thought for Gen X or anyone under the age of 18, who are losing ever more ground in the country’s demographic makeup. It’s the lingering effect of what Russell Baker, a New York Times humorist, termed “pigs in a python” in the 1970s. Baby boomers (the pigs) have spent decades moving through the U.S. economy (python), distorting everything in their path and leaving behind something unrecognizable.

Between 2020 and 2025, the number of people older than 65 rose 16.2%, according to the Census. The number of people between the ages of 25 and 44, broadly in line with the millennial cohort, increased 5.9%. Young adults barely held on to their ranks, with the 18-24 age range only rising 2.1%. 

The country is underwater, meanwhile, when it comes to kids and oft-neglected Gen Xers. The number of under-18-year-olds in the U.S. dipped 2.4%, while the population aged 45 to 64 declined 3.2%. These two demographic groups are shrinking in every part of the country except the South, the only corner of the U.S. that seems to be growing consistently at all. The region’s under-18 population grew 1.1%, while the number of Gen X-aged Americans rose a fractional 0.1%.

In the Census Bureau’s regional age breakdown, the South is the only region in the country that grew in all five age cohorts — children, young adults, early-career adults, midlife adults, and retirees — between April 2020 and July 2025. Every other region bled population in at least two categories, often more.

The South grew by 6% over that period. The nation as a whole grew by 3.1%.

The Northeast lost 4.1% of its under-18 population and 7.1% of its 45-to-64-year-olds — the steepest midlife decline of any region. The Midwest shed 3.9% of its children and 6.2% of its midlife cohort. The West, long the country’s demographic frontier, posted the worst child-population decline of any region: -5.7%.

“Regional age patterns are changing for a few key reasons,” said Lauren Bowers, chief of the Census Bureau’s Population Estimates branch. “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 Invisible Generation

There is a cohort in the middle of all of this that rarely gets a headline. Gen X — born roughly between 1965 and 1980, now aged 45 to 61 — maps almost precisely onto the Census Bureau’s 45-to-64 age bracket. And that bracket is shrinking in three of the country’s four regions: down 7.1% in the Northeast, 6.2% in the Midwest, 2.7% in the West. The South is the sole exception, and barely: a gain of 0.1%, roughly 19,000 people.

As the successors to baby boomers, Gen X never really stood a chance. The cohort was born during a period of plummeting fertility rates and changes to immigration policy. At around 65 million, the generation is smaller than both the baby boomers and the millennials that succeeded them. Statisticians have even referred to Gen X as the country’s forgotten “middle child,” given their ongoing struggle for relevance in demographic maps and the economy at large.

Gen X was always the overlooked cohort — sandwiched between the boomer cultural colossus and the millennial media obsession. Demographically, they are simply too small, compared to 76 million boomers and 72 million millennials. There weren’t enough of them to sustain regional population bases as boomers aged out, and there aren’t enough of them now to absorb the institutional, economic, and political weight that boomers are vacating.

They are also, in a quiet and underappreciated way, the load-bearing generation of the current American economy. Gen Xers are running the middle and upper-middle layers of corporate America — the VP floors, the managing director ranks, the regional leadership roles — while boomers hold on to the corner offices and millennials wait in line. When boomers finally cede control, Gen X won’t have the numbers to hold it for long.

Not all of the Census findings were necessarily surprises. The postwar boom in birth rates yielded one of the largest generations of all time as a share of the country at large. By the time the last baby boomer was born in 1964, the cohort comprised more than a third of the entire U.S. population. As immigrants added to the generation’s ranks over the years, baby boomers peaked in the 1990s at a massive 79 million.

The Peripheral Majority

Millennials — roughly 25 to 44 years old today — are the largest living generation in America. They are also, by the evidence of this data, the most economically sidelined.

The 25-to-44 cohort is growing fastest in the South. But that growth is concentrated in outlying metro counties — the exurban fringes of cities like Atlanta, Charlotte, Dallas, and Nashville. 

“The South’s growth from 2020 to 2025 has been particularly prominent in its metro areas’ outlying counties,” Bowers noted. “These outlying counties grew the fastest across all age groups, and often by a large margin, suggesting that they are attracting or retaining people of all ages.”

Why would that be? The economic answer is obvious. Millennials didn’t move to the exurbs of Raleigh and San Antonio because of opportunity. They moved because they were priced out of the cities where boomers own the housing stock and Gen X anchors the professional networks. The largest generation in American history is diffusing into economic margins, gaining square footage and losing proximity to power.

America’s aging population comes with real stakes for the country’s economy and political scene, a shift compounded by the steep decline in young populations almost anywhere in the country. But for now, the U.S. demographic shift is mostly representative of a baby boomer generation that remolded the country in its image, and of younger generations struggling to carve a piece out of it.