According to the first study to track marijuana use since Colorado legalized the drug for those over age 21 in 2012, Colorado has become the state with second highest percentage of regular marijuana users in the country.  The only state whose residents reported a higher rate of marijuana usage was Rhode Island.

According to the data, roughly one out of every eight Colorado residents over the age of 12 reported having used marijuana in the previous month.  Because these numbers are based on estimates gathered only in 2012 and 2013, the effects of commercial sales of marijuana since 2014 are still not known.

The number of marijuana users in Colorado was 10.4 percent for the 2011-2012 period, prior to the drug’s legalization.  That figure rose to 12.7 percent since its legalization, representing a 22 percent increase.  On  a national level, monthly marijuana use by individuals 12 years and older climbed upward to 7.4 percent, indicating a 4 percent increase from the prior period.  In Washington state, which also legalized the use and possession of marijuana in 2012, monthly marijuana use spiked about 20 percent to 12.3 percent.  The increase in marijuana use among Colorado residents for medical reasons rose during this same period.  Overall, roughly 530,000 Colorado residents use marijuana on a monthly basis.  The increase in monthly marijuana use was detected across all age groups.  There is no data in this study on daily marijuana usage, but this number is also believed to have surged considerably.

Another interesting note to emerge form this data is that researchers found an increase in the number of individuals also reporting alcohol and illegal drug use.  That number is expected to climb when estimates from 2014, which will include the data from commercial marijuana sales and purchases, are also evaluated.  However, despite claims by opponents of the 2012 law legalizing marijuana that it will lead to an increase in crime and automobile accidents in Colorado, the city of Denver has experienced a drop in crime rates.  In addition, automobile accidents are at historically low levels.