Yes, those old consumption estimates were way too low. Law enforcement seize way more every year than they said Americans consume, and you know law enforcement aren’t getting anywhere near two thirds or more of the pot on the market. I bet they’re probably only getting ten or twenty percent. At about the same time as those consumption estimates came out supply estimates came out where a different government agency claimed that the supply of marijuana available on the market here was between 12,000 and 25,000 metric tons per year, which is a little more than that consumption estimate of just over a 1000 metric tons per year. I think they must just make some of this crap up.
Sounds in line with Joe Arpaio's estimate:
"I don't know how to stop the drug traffic, and I've been in it for 38 years," the sheriff, widely touted as the toughest cop in the nation, told Harper's in 2001. "I think if I knew, I'd be the president. I can give you what's been said 50 years ago. ... It's the same thing we're saying today – tough law enforcement, prevention, rehabilitation ...
Nothing's changed. The stuff coming across the border that we catch? Ten percent. Fifty years ago, 10 percent. Today, 10 percent. Nothing's changed ... I don't know how to solve the problem. Don't ask me."
From WND article via http://www.freerepublic.com/focus/f-news/1156176/posts