The world’s most profitable crop?

This chart is from a beautiful infographic about cash crops.  I don’t believe the cannabis revenue number. That’s partly because I read Keith Humphreys and Mark Kleiman on the subject.

Keith Humphreys takes apart a claim of $120 billion for the total value of the US marijuana market, showing that it can’t be anything near that much.

Current pot smokers report that they use marijuana an average of 60 days a year. Using our current example, 40 ounces/60 days of use means that the average user would have to go through 2/3 of an ounce of marijuana on each day that they used marijuana. That’s .67 X 50 or 33.5 joints per day of use. And there’s a terrific bridge for sale in Brooklyn too.

Even then, the purported $120 billion was the price to the consumer.  That’s not what was used for the legal crops, and it makes a big difference.

Suppose we agree use consumer price rather than farmer revenue because the data are slightly more reliable. I don’t really believe a number above about $12 billion for the US.  The US has about 1/5 of the world GDP. If the US spent $12 billion/year on cannabis, the rest of the world would need to spend almost $300 billion, or more than six times as much as a fraction of their income.  A lot of the world would need to spend more on pot than on basic carbohydrates.

It’s not inconceivable that the number is right — maybe cannabis is really big in, say, Brazil or India and I just don’t know about it — but it’s surprising enough that I’d want a lot more detail to justify it.