For the first time in 45 years, homicide has fallen off the list of the nation's top causes of death.
U.S. Health officials say the murder rate fell enough in 2010 to drop it out of the top 15 causes. Criminologists have not reached a consensus about what's been driving murder rates down in recent years.
Meanwhile, death rates have been rising for diseases that kill the elderly. Moving up to take to homicide's place on the list was a respiratory condition that mainly kills people 75 and older. The top two causes of death are heart disease and cancer, which account for almost half of all U.S. deaths.