In the years since, violent crime has decreased in almost every city, in many cases by more than 75 percent. For well-off urbanites, the decline of crime is most visible in sanitized, closely guarded city spaces where tourists and others can now comfortably wander about. We found that the national decline in the homicide rate since then has increased the life expectancy of black men by roughly nine months. For example, researchers have estimated that if the obesity epidemic in the United States was eliminated, life expectancy would increase by a similar amount. The decline in violence on city streets also occurred inside public schools, creating environments where students could learn without fear of being victimized.

Source: New York Times January 13, 2018 19:52 UTC