“We’re looking for a neat, friendly roommate. Ideally you like to grab a drink or watch some TV from time to time.”

“Seeking someone mature. Otherwise, all demographics are welcome.”

“Nice, respectful, professionals looking for a roommate and occasional chat or a wine/beer/netflix buddy.”

Craigslist is full of people looking for roommates and shared living spaces—dirty dishes and squabbles over laundry machines be damned. An analysis from Priceonomics shows that 18 to 39-year-olds in Arlington and Washington D.C. are the second and fourth most likely to be living with roommates. San Francisco comes in at number one.

In Arlington, 23 percent of young folks live with people who aren’t their family or spouses. In D.C., it’s 21 percent. The average of the top 50 cities is 12 percent.

In general, the share of Americans with roomies has increased over the course of the last 50 years. According to Priceonomics, “Combine increased urbanization, lower marriage rates, later marriage, and increasingly expensive housing costs, and you get a lot of young people willing to live with friends and strangers.”

D.C. has one of the highest rates of singles in the country, a fact used more often to remark on the dating scene than the real estate market. Pair that with the average cost of housing in District being third-highest in the country, and you’ve got a potent combination for communal living.

Both Arlington and D.C. made the top ten list for places where 30-somethings are most likely to have roommates, termed the “Peter Pan syndrome.” Arlington comes in third and D.C. eighth.

Hat tip to Greater Greater Washington.