The Centers for Disease Control and Prevention (CDC) published in 2000 a study on dog bite-related fatalities (DBRF) that covered the years 1979–1998. The study found reports of 238 people killed by dogs over the 24-year period, of which "pit bull terrier" or mixes thereof were reportedly responsible for killing 76, or about 32 percent, of the people killed by dogs in the attacks identified in the study. The breed with the next-highest number of attributed fatalities was the Rottweiler and mixes thereof, with 44 fatalities or about 18 percent of the study-identified fatalities. In aggregate, pit bulls, Rottweilers, and mixes thereof were involved in about 50% of the fatalities identified over the 20-year period covered by the study, and for 67% of the DBRF reported in the final two years studied (1997–1998), concluding