The number of high-school aged Americans who self-report having sex has declined noticeably over the last decade, according to a new report released by the Center for Disease Control (CDC) on Thursday.
That trend includes "substantial declines" among younger, black, and Hispanic students, the Washington Post reports. The overall declines have been particularly notable in the past two years.
According to the analyzed survey, the National Youth Risk Behavior Survey, 41.2 percent of high school students self-report having had sexual intercourse in 2015. That's a drop from 46.8 percent in 2013, a rate in turn on par with 2005 numbers.
The drops were more pronounced among Hispanic students, where the proportion of students self-reporting having had sex dropped from 49.2 to 42.5 percent. The decline among white students was smaller, from 43.7 to 39.9 percent over the 2013 to 2015 period.
Teens are overall engaging in less risky behavior, with both teen pregnancy and use of marijuana among the same cohort having reached 20 year lows.
This is all good news, as early sexual activity is correlated with a greater likelihood of irresponsible sexual choices later down the road.
"Early initiation of sexual activity is associated with having more sexual partners, not using condoms, sexually transmitted infection and pregnancy during adolescence," the report noted.
Researchers did not offer a single explanation for the decline, saying they could not attribute it "directly to any specific intervention." Laura Lindberg, a research scientist with the left-leaning Guttmacher institute, cautioned in an interview with the Post that the recent substantial declines may just be a "blip."
"We need to see if this is a short-term blip or this is something that is going to continue," Lindberg said. "The drops are very large in 2015, and that raises questions of survey value."
The report released Thursday do deviate from another survey, which showed negligible change in teenage sexual behavior. The former was conducted in schools, while the latter was conducted in teens' homes.