CBS Local — While today’s teens may have many odd habits their parents don’t understand, a recent study has found that American adolescents are getting into much less trouble than previous generations.

A 12-year survey from 2003 to 2014 found that teens are less likely to start doing drugs, having underage sex, or committing crimes. Researchers at Washington University School of Medicine in St. Louis looked at data on over 210,000 children between the ages of 12 and 17 in every state.

While the study found similar patterns in the decline of drug use among teens, lead researcher Richard Grucza says his team found a link to the decrease in crimes like fighting and stealing as well.

“What we learned in this study is that the declines in substance abuse are connected to declines in delinquency,” Grucza said in a press release. “This suggests the changes have been driven more by changes in adolescents themselves more than by policies to reduce substance abuse.”

The study also pointed to a greater focus on mental health and substance abuse prevention for the drop in teen crimes since the 1990’s. Grucza’s team claims drops in lead exposure, child abuse and neglect, and increased focus on disorders like ADHD have all contributed to teens living cleaner lives in 2017.

“This study is really good news, especially with the opioid crisis just announced as a public health emergency,” Grucza added.

A previous study of eight million teens found that nearly half the number of adolescents since 2010 have tried alcohol compared to teens in the 1990’s. That survey also said that while today’s teens were getting into less risky situations, they were also working, dating, and driving less as well.