This 2007 paper titled Helping Settle the Marijuana and Alcohol Debate: Evidence from Scanner Data is a must read and can be accessed by Clicking Here. This document has something for everyone buts its key findings, as it relates to this case study, are:
Alcohol Sales Have Dropped as Much as 13% in States
Where Cannabis Has Become Legal
Based on scanner data for alcohol sales 2006-2015 in
states that have enacted medical cannabis programs
Switching may exist to an even greater extent in states
where recreational cannabis is legal
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