In case you missed it Move-On .Org sent out an e-mail on 9/11/07 to refute the claims General Petraeus was making before Congress regarding a lessening of violence in Iraq. The following is a paragraph taken from that e-mail.
"Petraeus is using "funny math." According to the Washington Post, Petraeus and the Pentagon are using a bizarre formula for measuring violence in the country. For example, deaths by car bombs don't count.3 And assassinations count only if you're shot in the back of the head-not in the front.4"
For related background material on this subject there is an article by Paul Krugman of the New York Times, Sept. 7, 2007 titled "Time to take a stand".