Great Graphic: Up in Smoke? Rhode Island?

This Great Graphic was posted on Vox by German Lopez, who found it on Statistica.Com, where it was posted by Niall McCarthy.  It shows the US states that have the highest percentage of it population (over the age of 12) admitting to having smoked marijuana in the past month.  

Surprisingly, the dubious honor does not go to Colorado or Washington where legalization has taken place.  Rather it looks like Rhode Island, Alaska and Vermont take the prize.  More than one in eight have lit up in the past month.  

This year voters in Alaska, Oregon and the District of Columbia will vote on the marijuana legalization.  Polls suggest there is a good chance of passage.  

It is not immediately clear the impact of legalization on marijuana use.  It has been too recent of a phenomenon.  Consider Colorado became the first state to legalize it in late 2012.  It did not go into effect until the start of this year.  We do know that the number of high school students who admit to smoking it in the past month fell in 2013 to 20% from 22% in 2011.   However, the change is not statistically significant, according to the Colorado Department of Public Health and Environment.  

On the other hand, about six months after the legalization took affect, the Colorado Department of Revenue reported that the demand for legal marijuana was projected to be nearly a third higher than it had previously estimated, and nearly 90% more than the frequently cited projection by the Colorado Futures Center. Reports do suggest, however, that there medical marijuana use has been relative constant.  The legalization does not appear to have shifted demand from medical to recreation use. Recreation use simply increased.