In the 19th century gun violence played a role in civil disorder such as the Haymarket riot.[82] Homicide rates in cities such as Philadelphia were significantly lower in the 19th century than in modern times.[83] During the 1980s and early 1990s, homicide rates surged in cities across the United States (see graphs at right).[84] Handgun homicides accounted for nearly all of the overall increase in the homicide rate, from 1985 to 1993, while homicide rates involving other weapons declined during that time frame.[38] The rising trend in homicide rates during the 1980s and early 1990s was most pronounced among lower income and especially unemployed males. Youths and Hispanic and African American males in the U.S. were the most represented, with the injury and death rates tripling for black males aged 13 through 17 and doubling for black males aged 18 through 24.[85][72] The rise in crack cocaine use in cities across the U.S. is often cited as a factor for increased gun violence among youths during this time period.[86][87][88]