Beyond just a drop in alcohol use and sexual activity, the study authors found that since around 2000, teens have become considerably less likely to drive, have an after-school job and date. By the early 2010s, it also appeared that 12th graders were going out far less frequently than 8th graders did in the 1990s. In 1991 54 percent of high schoolers reported having had sex at least once; in 2015 the number was down to 41 percent. What’s more, the decline in adult activity was consistent across all populations, and not influenced by race, gender or location. “I’ve seen so many articles in which experts said they didn’t know why the teen pregnancy rate was going down or opining that teens were behaving in a more virtuous way…or that they were lazy because fewer were working,” recalls Jean Twenge, professor of psychology at San Diego State and the lead author on the study. “Our results show that it’s probably not that today’s teens are more virtuous, or more lazy—it’s just that they’re less likely to do adult things.” She adds that in terms of adult behaviors, 18-year-olds now look like 15-year-olds of the past.