The number of people living in the average American home is shrinking, according to a report from Realtor.com, leaving many homes with more bedrooms than they need.

Analyzing U.S. Census Bureau data from 1970 through 2023, as well as data on the 100 largest U.S. metropolitan areas, researchers found that the number and share of “excess bedrooms” reached a record high in 2023. To determine the amount of excess bedrooms, researchers subtracted the total number of household members from the number of bedrooms in a given metro area. They then subtracted one from that number, acknowledging that a spare bedroom is often used as an office or storage space.