A study [4] commissioned by Colorado's Marijuana Enforcement Division this year [5] found that people who use marijuana almost every day account for about 22 percent of cannabis users in Colorado but consume nearly 67 percent of the marijuana used. Other studies [6] have warned about a possible uptick in heavy marijuana use.
Links
[1] http://www.denverpost.com/news/ci_27212493/marijuana-use-increases-colorado-according-new-federal-survey
[2] http://www.rethinkpot.org/tags/colorado%2A
[3] http://www.rethinkpot.org/tags/colorado-0
[4] https://www.colorado.gov/pacific/sites/default/files/Market%20Size%20and%20Demand%20Study%2C%20July%209%2C%202014%5B1%5D_0.pdf
[5] http://www.denverpost.com/news/ci_26119492/colorado-estimates-state-annual-pot-consumption-at-130
[6] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3818642/