"The NCVS collects information on nonfatal crimes, reported and not reported to the police, against persons age 12 or older from a nationally representative sample of U.S. households. It produces national rates and levels of personal and property victimization, as well as information on the characteristics of crimes and victims and the consequences of victimization to victims. Violent crimes measured by the NCVS include rape, sexual assault, robbery, aggravated assault, and simple assault. Property crimes include household burglary, motor vehicle theft, and theft. The survey also measures personal theft, including pocket picking and purse snatching. In 2008, 42,093 households and 77,852 individuals age 12 and older were interviewed for the NCVS. Each household was interviewed twice during the year. The response rate was 90.4% of households and 86.2% of eligible individuals. Violent and property crime rates remain at historic lows in 2008."
Bureau of Justice Statistics: NCJ 227777
U.S. Department of Justice, Bureau of Justice Statistics: http://www.ncjrs.gov/