The average American household size is on the rise for the first time in over a century, and it's partly because millennials can't afford to live by themselves
- The average American household size has increased for the first time in more than 160 years, according to the Pew Research Center.
- Pew researcher Richard Fry said the trend is related to an increase in both the number of multigenerational family households and the number of Americans living in shared quarters.
- As millennials play catch up from the Great Recession and struggle to afford soaring rent and housing prices, they're doubling up to save money.
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The average American household size is on the rise - for the first time in 160-plus years.
From 1790 to 2010, the average US household size declined from 5.79 people to 2.58, according to a Pew Research Center analysis of US Census data. In 2018, that number saw an uptick for the first time since 1850 (Pew noted that average household size is not available for the years between 1790 and 1850), with 2.63 people per household. While this trend is seen among most age groups, it's most prominent among adults ages 35 and older.
Pew researcher Richard Fry wrote that the previous decline in household size correlated with the decrease in the number of children women were having, as well as fewer extended family living arrangements.
The uptick is likely due to several factors, Fry wrote. For one thing, from 1980 to 2016, the number of Americans living in a multigenerational family household has increased from 12% to 20%.
There's also the fact that, since the Great Recession, more Americans are residing in shared quarters, whether it's with a roommate or with parents, Fry wrote. The number of shared households increased from 17% to 20% from 2007 to 2019, he said.
Read more: The 25 US cities where the most millennials still live with their parents, ranked
Millennials are doubling up to afford housing and save money
The Great Recession left millennials, particularly the older cohort, playing catch up with their finances. As they struggled with wage stagnation, student-loan debt, and rising living costs, it became difficult for them to save. That's not to mention today's housing market: Both rent and home prices have increased exponentially since the 1980s, according to Student Loan Hero.
As Allie Volpe previously reported for The Atlantic, the number of Americans aged 18 to 34 with roommates increased by 23% from 2005 to 2015, according to the US Census Bureau.
Consider the 35% of millennials still living with their parents, according to Country Financial's Security Index. Doyle Williams, an executive vice president at Country Financial, said in a press release that this time can give millennials the chance to build an emergency fund and save for a down payment.
There's also the rise of communal living, or "co-living" spaces, in urban areas like New York and San Francisco.
"The market for communal living, or 'co-living,' spaces is quickly crowding," wrote Business Insider's Melia Robinson, adding that they're "competing for millennials' dollars as young people continue moving to high-priced urban areas."
Living with others is becoming a necessity to cut costs in trying times.