Maybe it’s hookup culture. Maybe it’s that people are getting married later in life. Or maybe it’s that people struggle to meet potential partners in person nowadays.

The number of young Americans who are single has reached its peak since at least the 1980s — it’s now more than half, according to a study released this week — and has drastically increased in the last 15 years.

That’s according to data from a General Social Survey released this week. In 2018, 51 percent of Americans ages 18 to 34 said they didn’t have a “steady partner," up from 33 percent in 2004. The figure was 35 percent in 1986, the first year the question was asked as part of the survey.

Among the same age group, 28 percent of respondents said they were married, down from 39 percent in 2004 and 48 percent in 1986. The data were compiled by researchers at the University of Chicago who conducted in-person interviews with a random sample of more than 2,000 adults.

The data may seem counter-intuitive at a time when dating feels more accessible than ever as a result of the proliferation of apps. In 2017, four in 10 singles had met their most recent first date on the internet, more than those who met “through a friend” or “at a bar” combined, according to results from the Singles in America survey, a Match.com-sponsored survey of 5,000 people nationwide.

But the relative speed of finding a potential partner right at your fingertips apparently hasn’t translated to a higher overall percentage of young people in committed relationships. In fact, the data may illustrate that a greater number of people have multiple love interests, none of whom is a “steady partner.”

Thomas Edwards Jr., a dating coach and founder of the Professional Wingman, said the accessibility of a potential partner provided by the dating apps and seemingly infinite swiping tends to be something people take for granted.

“Access is so rampant,” he said, “and so it makes us feel like, ‘Well, I have access to potential partners at my fingertips, I don’t need to do so much, because the access will always be there.’ So we fall into this state of complacency.”

There are a few other trends at work. One is that people are getting married later in life (and women are having fewer children and later in their lives). In 2018, the median age for a first marriage was 27.8 for women and 29.8 for men, about four years older than the median ages in 1986, which were 23.1 for women and 25.7 for men, according to U.S. Census Bureau data.

The major reasons Americans cited for not being married was that they either hadn’t found the “right person” or weren’t financially stable, according to a Pew Research Center survey conducted in 2017 among nearly 5,000 U.S. adults. Among the adults surveyed who had never been married but were open to the possibility, about six in 10 said a major reason was that they “have not found the right person.”

Among young people ages 18 to 29, about half said not being financially stable was a major reason they weren’t married. Studies show more young people are electing to live at home while saving cash as home prices, rent costs, and student loan debt are rising at a faster rate than income.

Edwards said he often works with clients who live at home or don’t have a steady career and see that as a reason to avoid pursuing a relationship.

“It’s the new comfort zone,” he said. “Working and creating financial stability and being into yourself is the new comfort zone, whereas putting yourself out there and seeking connection with the risk of rejection is something people don’t want to do.”