[HungLikeJesus]

It's pretty easy to find dog bite statistics by breed. This site is focused on the US, but there's some interesting information. Here's just one quote:

The deadliest dogs

Merritt Clifton, editor of Animal People, has conducted an unusually detailed study of dog bites from 1982 to the present. (Clifton, Dog attack deaths and maimings, U.S. & Canada, September 1982 to November 13, 2006; click here to read it.) The Clifton study show the number of serious canine-inflicted injuries by breed. The author's observations about the breeds and generally how to deal with the dangerous dog problem are enlightening.
According to the Clifton study, pit bulls, Rottweilers, Presa Canarios and their mixes are responsible for 74% of attacks that were included in the study, 68% of the attacks upon children, 82% of the attacks upon adults, 65% of the deaths, and 68% of the maimings. In more than two-thirds of the cases included in the study, the life-threatening or fatal attack was apparently the first known dangerous behavior by the animal in question. Clifton states:

If almost any other dog has a bad moment, someone may get bitten, but will not be maimed for life or killed, and the actuarial risk is accordingly reasonable. If a pit bull terrier or a Rottweiler has a bad moment, often someone is maimed or killed--and that has now created off-the-chart actuarial risk, for which the dogs as well as their victims are paying the price.

That supports what DanaC and some others have posted.