Fans of The Wire already know how police departments cook crime stats. Today the New York Times reports on how school systems use fuzzy math to come up with graduation rates:

One team of statisticians working at the state education headquarters here recently calculated the official graduation rate at a respectable 87 percent, which Mississippi reported to Washington. But in another office piled with computer printouts, a second team of number crunchers came up with a different rate: a more sobering 63 percent.

The state schools superintendent, Hank Bounds, says the lower rate is more accurate and uses it in a campaign to combat a dropout crisis.