Business:

Report shows San Jose and S.F. metropolitan areas have the highest median rents, renter household incomes in the nation.

The share of Bay Area households that rent their homes has grown significantly over the last decade — by about 5 percent — while the share that own their homes has declined in kind.

That change in lifestyle — part of a national trend — is pinpointed by a new study of rental patterns in the 53 largest U.S. metropolitan areas. It also shows that the San Jose and San Francisco metro areas have the nation’s highest median rents and renter household incomes, that their rental populations have increasing numbers of high-income and college- educated members — and that the burden of paying rent here is considerable, nonetheless.

In the San Jose metro area, 45.1 percent of all renter households are “rent burdened,” meaning that more than 30 percent of their pre-tax income goes to paying monthly rent, according to the report by New York University’s Furman Center for Real Estate and Urban Policy.

But the burden increases for renter households in the San Jose metro area earning less than $ 50,000. Among those households, 83 percent are “rent burdened” — and 56.5 percent are “severely rent burdened,” meaning that housing eats up more than 50 percent of their income.

The figures are similarly dramatic in the San Francisco metro area, which includesOakland, aswell as all

of Alameda, Contra Costa, SanMateo and Marin counties. There and throughout Silicon Valley — and most of the country — there is “a change in rent composition,” said Sewin Chan, a professor of public policy who coauthored the study. “There’s more renters and more of them have high income and higher education. So that’s sort of masking an affordability problem for people at the lower end” of the income spectrum.

The study, which looks at U.S. Census data from 2006 to 2015, does not identify specific reasons for the change in composition of the renter population. But it adds a new layer of evidence that more Americans are opting for apartment living.

That may partly be due to the fact that many homeowners went into foreclosure during theGreat Recession and haven’t been able to get back into the real estate market, especially in a place like the Bay Area where the median price of a singlefamily home now tops $1 million in several counties. But itmay also be because so many people — millennials, in particular — have come to prefer the rental lifestyle, where it’s easy to pick up and move to the next job and the next city.

“Maybe there’s just less of a stigma to renting than there was before,” said Stephanie Rosoff, a project director for the new report, titled “2017 National Rental Housing Landscape: Renting in the Nation’s Largest Metros.”

In the San Jose metro area, which includes Santa Clara and San Benito counties, 43.7 percent of all households rented their homes in 2015, up from39.2 percent in 2006. In the San Francisco metro area, there was a similar jump: to 46.3 percent in 2015, from 41.5 percent in 2006.

During the same time period, the share of households that owned their own homes fell from60.8 percent to 56.3 percent in the San Jose metro area and from 58.5 percent to 53.7 percent in the San Francisco metro area.

Among the report’s other findings is that when renters change apartments in the San Jose and San Francisco metro areas— or move from outside the area to an apartment here — they in effect pay a “premium” on their rent.

For instance, in 2015, the median rent for a two-bedroom unit in the San Jose metro area was $1,850. But recently available two-bedroom flats — those that had new occupants within the previous 12 months — had a median rent of $2,460. In other words, moving to another two-bedroom flat meant coughing up an extra $610 a month. In the San Francisco metro area, the “premium” was $470.

Among the 53 metro areas in the study, those are the twowith themost costly “premiums” for switching apartments. And in both of those metros, there was a sharp drop in the share of lower-income households that can afford to move to recently available apartments.

“Recent movers are paying higher rents than people who haven’t moved,” Chan said. “And we’re seeing this ismore of a problemin highrent cities. It’s kind of what you would expect when rents are going up rapidly in a metro — landlords are going to be charging higher rents as they change their tenants.”

In the San Jose metro area, the share of renter households earning 120 percent or more of the area’s median household income was 29.2 percent in 2015, when the median was $100,000. That share of high-income households was up from 21.8 percent in 2006, when themedian was $93,820. During the same period, the share of renter households with a college degree rose from 45.5 percent to 53.1 percent.

Paradoxically, the share of “burdened” renter households rose over the course of the decade in the San Jose metro area — but dipped between 2012 and 2015 when the tech-fueled economy was helping to drive up housing prices.

It’s “because wealthier people are renting,” Rosoff explained.