A 9-year (1979–88) review of fatal dog attacks in the United States determined that, of the 101 attacks in which breed was recorded, pit bulls were implicated in 42 of those attacks (42%).[24] A 1991 study found that 94% of attacks on children by pit bulls were unprovoked, compared to 43% for other breeds.[25] A 5-year (1989–94) review of fatal dog attacks in the U.S. determined that pit bulls and pit bull mixed breeds were implicated in 24 (29%) of the 84 deaths in which breed was recorded.[26]
A 20-year (1979-1998) study by the American Veterinary Medical Association into fatal dog attacks on humans[27] concluded that "fatal attacks on humans appear to be a breed-specific problem (pit bull-type dogs and Rottweilers)," and that "pit bull-type dogs and Rottweilers were involved in more than half" (67%) of all the 238 recorded dog bite-related fatalities (DBRF) in the United States during that period, with pit bulls accounting for 66 deaths. They also wrote that:
"It is extremely unlikely that they accounted for anywhere near 60% of dogs in the United States during that same period and, thus, there appears to be a breed-specific problem with fatalities."[27]
Long story short, there's no doubt that there's a lot of external factors such as ownership, how the dog was raised, etc. But you're simply ignorant if you don't think the breed is naturally aggressive.
