The number of chronic marijuana users–defined as those who used it on four or more days in the past month–increased 84.3% between 2000 to 2010, according to a RAND Corporation report commissioned by the White House.

“In January 2012, the U.S. White House Office of National Drug Control Policy (ONDCP) asked RAND to generate national estimates of the total number of users, total expenditures, and total consumption for four illicit drugs from 2000 to 2010: cocaine (including crack), heroin, marijuana, and methamphetamine (or meth),” says the report, What America’s Users Spend on Illicit Drugs: 2000-2010.

According to the report, chronic marijuana users climbed from 7,000,000 in 2000 and to a high of 12,900,000 in 2010–an increase of 5,900,000 or 84.3 percent.