Have you heard? Meth use is down. Both in terms of overal use and the number of new users.

So says a National Survey on Drug Use and Health report. In contrast to the heavy coverage of a meth "epidemic" in recent years, though, this federal report has gotten next to no mention.

Jack Shafer, Slate's media critic, lays out the reasons why news of increased use is news, while news of decreases are ignored.