"In 2010, approximately 2.8 million children, representing 3.9% of all children age 17 or younger living in U.S. households, lived in a household in which at least one member age 12 or older experienced one or more nonfatal violent victimizations during the year (figure 1). This was a decline from 1993, when an estimated 8.7 million children, or 12.6% of all children age 17 or younger, lived in a household that experienced a violent victimization. The decline in the number of children living in a household in which at least one member experienced violent crime corresponds with the decline in overall violent victimization during the same period. [...] This report measures violent crime involving members of a household as victims, and reports on the annual prevalence of that violent crime among U.S. households with children from 1993 to 2010. The prevalence rate is the percentage of unique households in which at least one member age 12 or older experienced a violent victimization in a given year, regardless of the number or frequency of victimizations or the different types of victimizations those households experienced. The prevalence rate differs from the incident-based violent victimization rates commonly reported in statistics developed from the NCVS [National Crime Victimization Survey]."
Bureau of Justice Statistics: http://www.bjs.gov/