A new study says that marijuana usage in America has doubled over the last decade. Researchers collected data from more than 36,000 people in 2012-2013, posting their findings in the journal JAMA Psychiatry. 9.5% admitted they used the drug, compared to the $4.1% in the previous decade, which surveyed 43,000 adults. According to Time, middle-aged adults and senior citizens were among the highest rates.

But with great usage comes addiction, and the study also shows that that percentage has gone up as well. Cases of addiction and abuse have increased to 2.9%, which is almost twice as much as the 1.5% in the decade before that. A press release explained that this number “means nearly 3 of every 10 Americans who used marijuana in the past year had a diagnosis of a marijuana use disorder (approximately 6.8 million Americans).” Those affected the most? African American and Hispanic people.