For the first time since the end of the Great Depression, more young adults are living with their parents than not, according to a recent report from the Pew Research Center.

It’s yet another impact of the COVID-19 pandemic, which persists across the U.S. even as the housing market shows resilience to its effects. Per Pew’s data, 52% of adults aged between 18 and 29 years — some 26.6 million people — lived with one or both of their parents in July, rising from 47% in February before the outbreak took hold of the country.

That increase represents 2.6 million young adults moving back into their parents’ homes in five months. Before this year, the highest share of young adults living with their parents was 48%, measured during the 1940 Census, right after the close of the Depression. (Pew notes that the peak may have been higher during the Depression itself, but there’s no data for that timeframe.)

With the coronavirus outbreak ongoing, however, that level has stayed above 50% every month this year since April. Nine percent — almost one in 10 — of young adults in Pew’s survey say they relocated temporarily or permanently due to the pandemic, with nearly the same percentage (10%) having someone move into their household.

Eighty-eight percent of those who moved now live in their parents’ homes, with almost all of the rest living in their own homes with their parents or in homes headed by other family members.

Some of the gain in young adults living with their parents can be attributed to simple seasonality; the share typically grows a little in the summer after college final exams. That gain, however, is usually trivial; last year, for example, the share of young adults sharing a residence with their parents increased by a small amount: less than two percentage points. This year’s much sharper jump again shows the pandemic’s drastic effect.

And indeed, among those who moved, 23% said that the most important reason was that their college campuses had closed, the most cited reason in the survey. Perhaps accordingly, 2.1 million of the youngest adults (18-24 years old) accounted for most of the increase from February to July. Most of that group already lived with their parents, but that level rose from 63% in February to 71% in July. Pew noted that the survey counted unmarried students who lived in on-campus college dorms as already living with their parents, so while many campuses have been shuttered, any increase isn’t due to the closures of dorms in the spring.

Another 18% of survey respondents indicated that it was due to job loss or “other financial reasons.” This is consistent with employment losses since the outbreak began, since the youngest adults have been more likely than other age brackets to either lose their jobs or see their pay decrease during that time, according to other Pew studies.