I haven't read the methodology for how the bureau of labor statistics gets its data, but I'd be very surprised if it were significantly flawed. The federal government is generally extremely competent at collecting social sciences data like this. I'd actually say that it's one of the few things the government does really well.
The big thing you need to watch out for is the media and other government agencies spinning it. For example I always see MSM articles saying that 41% of Americans have tried weed, despite the fact that it's closer to 85% of Americans under age 55.[1] (And above that we don't have as good data.)
The big thing you need to watch out for is the media and other government agencies spinning it. For example I always see MSM articles saying that 41% of Americans have tried weed, despite the fact that it's closer to 85% of Americans under age 55.[1] (And above that we don't have as good data.)
[1] http://www.erowid.org/psychoactives/statistics/statistics_ar...