Single households tend to use more transit and live in multi-family homes.
Whatever you want to call people living alone — some go with solos, others singletons — the fact is there's a lot more of them than there used to be. In 1950, solos accounted for about 9 percent of all U.S. households; today that figure is roughly 28 percent. As sociologist Eric Klinenberg points out in his 2012 book Going Solo, one in seven American adults now lives alone, and the trend toward solitary living is truly global:
For the first time in human history, great numbers of people — at all ages, in all places, of every political persuasion — have begun settling down as singletons.
Solos may settle down in all places, but the places they seem to prefer most are central cities. That's significant, says Devajyoti Deka of the Alan M. Voorhees Transport Centre at Rutgers, because when it comes to housing and travel preferences, solos tend to live more sustainable lifestyles. The more sustainable people move into cities, the more sustainable those cities are likely to become.
"If solos continue to grow, even from cross-sectional data it appears that cities will be more sustainable," says Deka. "They are much less likely to live in single-family homes. They're more likely to live in apartments. They commute shorter distances. They spend less time commuting to work. They use public transit more often."
Indeed, Deka has tracked the behavioral trends of solos and found them to be far more sustainable than those of married people across the board. When it comes to housing, for instance, roughly half of solos live in rented dwellings compared to about a quarter of couples. While three-quarters of couples live in detached single-family homes that characterize suburban sprawl, that's only true for about 45 percent of solo men and 48 percent of solo women.
The travel data shows more of the same. Solos live about three miles closer to work than couples, on average, and are much more likely to commute by transit, with a roughly 6 to 7 percent transit share for solos versus about 3 percent for couples. Solos are less likely to travel anywhere by car, and while nearly all couple households own at least one automobile, that's only true for about 85 percent of solo households.
Part of the reason so many solos flock to the city, says Deka, is that they earn more there than they do outside of it. In a paper set for publication in Urban Studies, Deka shows that solo men and women each make at least $5,000 more a year when they live in the city. On the contrary, male earners in married couples (and to a lesser extent female earners) make about the same in the city as they do in general.
Deka attributes the increased earnings of urban solos to their employment flexibility. His data show that solos are much less likely than married people to move to get a bigger home, for instance, and much more likely to move to be closer to work. In everyday terms, if an employer offers a solo $20,000 more to move cities, that solo has far fewer barriers to accepting the job.
"Solos can optimize their earning power when they move," says Deka. "But a married person would be constrained and they may give up the increase in salary earnings."
But the paradox of solo attraction to urban life is that modern metro areas were largely planned and designed with the nuclear family in mind. As a result, if cities want to keep the solos coming, they will have to make it worth their while. Indeed, solos have already slipped, between 1990 and 2010, in terms of transit use and car ownership.
Deka says there are two things cities must do to retain their solo edge. The first is to promote and enhance public transportation, which of course most are doing for sustainable reasons anyway. The second is to recognize that, contrary to much popular belief, there are twice as many elderly solos (above 65) than young ones (18 to 34).
That raises two additional problems for cities that hope to attract and keep solos. One is the need to develop better housing for the elderly — be it affordable and livable single-occupancy studios or nicer nursing homes. The other is figuring out a way to improve mobility for older people, including the expensive paratransit services upon which they so often rely.
These changes might be costly, says Deka, but considering how much solos give to cities in terms of economics and sustainability, they aren't too much to ask in return.
"If solos contribute to the economy and they are beneficial to society for all their adult active lives," he says, "they should have contributed enough to get social support in the transportation when they become old."