The World Needs More Ninjas

One thing that amuses me is seeing statistics being completely abused. For an entertaining read on the matter, I’d recommend this book.

So, one of the latest media and government frenzies seems to be about meth use. The federal government now has a website that links to this website from the Tennessee District Attorney’s General Association. According to the latter site, if you look at the Fast Facts at the bottom, you should be scared stupid by the alarming usage among high schoolers. Let’s do a little math (not to be confused with meth). We’ll be keeping a running total of what percentage of high school students fall into each category of the meth statistics.

• 1 in 7 high school students will try meth = 14.3%
• Of these, 99 percent of first-time meth users are hooked after just the first try = 14.3 * 0.99 = 14.1%
• Of these, only 5 percent of meth addicts are able to kick it and stay away = 14.1 * 0.95 = 13.4%
• Finally, from the first hit to the last breath, the life expectancy of a habitual meth user is only 5 years.

Thus, 13.4% of high schoolers should die of meth use within 5 years of finishing school. According to the US Census Bureau, as of Oct. 2003, there were just over 17 million students enrolled in high school. Thus, we would expect the death rate of meth usage to be about 2.28 million people per year (17 million * 0.134) from this demographic alone. By contrast, a total of about 1.19 million Americans have died in every war that was ever fought by the US. Holy crap, we have a national epidemic on our hands, right?

Uh, not exactly. In 1998, the last year for which I could find statistics, there were about 500 meth-related deaths. Assuming that every one of these deaths was a high schooler, we have a death rate of 0.003% from meth (500/17 million * 100%). In other words, the 13.4% statistic is wrong by a factor of over 4000 (13.4 / 0.003).