According to calculations by researchers at the Guttmacher Institute in New York, the Pregnancy Risk Index for teens is steadily falling—by about 5.6 percent each year.

That’s thanks to an increased use of contraceptives found among the 3,000 young women age 15 to 19 interviewed for the study. About a third of the subjects were sexually active throughout the study (between 2007 and 2012), a rate that did not change. But as the interviews progress, researchers found that more of the girls were using contraception (78 percent at the start vs. 86 percent at the end) and some were even using more than one method (26 percent at the start to 37 percent by the end).

Those stats confirmed to researchers that it was the increased use of contraception, not a declining rate in teen sex, that caused the falling Pregnancy Risk Index. One researcher praised teens “considered and responsible decisions” for the change.

Check out the New York Times for more details on the study and its findings.