Percentage of high school students involved in selected behaviors that may endanger their safety: 1991, 1999, and 2009
1 One or more times during the 30 days preceding the survey.
2 Examples of a weapon are a gun, knife, or club.
3 One or more times during the 12 months preceding the survey.
4 Physical fight resulting in injury requiring attention by a doctor or nurse.
SOURCE: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention (CDC), Morbidity and Mortality Weekly Report, Youth Risk Behavior Surveillance—United States, 1991, 1999, and 2009.