The Centers for Disease Control released a monster report in May on the state of Americans' health. The 511-page report makes one thing abundantly clear: teens are behaving better right now than pretty much any other time since the federal government began collecting data.

The teen birth rate is at an all-time low

The teen birth rate has plummeted in recent decades. Separate data shows this has coincided with dramatic drops in the teen abortion rates. Nobody is totally sure why this is happening, but they do have a lot of theories about why its happening, which range from the show 16 and Pregnant setting a good example to getting lead out of the environment.

Fewer teens are having unprotected sex

The decline in teen births has also happened at a time when teenagers have gotten better at using contraceptives. Over 30 percent of teenagers between 15 and 19 report using contraceptives, which is up from 24 percent in 1982 (it is a slight drop, however, from 2002).

High school seniors are drinking less, smoking less, and barely using cocaine

Instead, they're… exercising more?

The CDC unfortunately doesn't measure how many teenagers specifically are meeting federal exercise guidelines (which recommend at least an hour of exercise three days per week). But they do look at 18 to 24-year-olds, who have the highest rate of hitting the federal guidelines among any group of adults measured — and have been doing better in recent years.