U.S. Department of Justice Office of Justice Programs Bureau of Justice Statistics ----------------------------------------------------------------- This file is text only without graphics and many of the tables. A Zip archive of the tables in this report in spreadsheet format (.csv) and the full report including tables and graphics in .pdf format are available on BJS website at: http://www.bjs.gov/index.cfm?ty=pbdetail&iid=5804 This report is one in a series. More recent editions may be available. To view a list of all in the series go to http://bjs.gov/index.cfm?ty=pbse&sid=6 ----------------------------------------------------------------- ********** Bulletin ********* ********************************* Criminal Victimization, 2015 ********************************* Jennifer L. Truman, Ph.D., and Rachel E. Morgan, Ph.D., BJS Statisticians In 2015, U.S. residents age 12 or older experienced an estimated 5.0 million violent victimizations, according to the Bureau of Justice Statistics’ (BJS) National Crime Victimization Survey (NCVS). ***Footnote *Unless otherwise noted, the findings in this report are at the95% confidence level.*** There was no statistically significant change in the rate of overall violent crime, defined as rape or sexual assault, robbery, aggravated assault, and simple assault, from 2014 (20.1 victimizations per 1,000 persons age 12 and older) to 2015 (18.6 per 1,000) (figure 1). However, the rate of violent crime in 2015 was lower than in 2013 (23.2 per 1,000). From 1993 to 2015, the rate of violent crime declined from 79.8 to 18.6 victimizations per 1,000 persons age 12 or older. The rates of violent and property crime largely followed similar trends over time. Households in the U.S. experienced an estimated 14.6 million property victimizations in 2015 (see table 3). The overall property crime rate (which includes household burglary, theft, and motor vehicle theft) decreased from 118.1 victimizations per 1,000 households in 2014 to 110.7 victimizations per 1,000 in 2015. A decline in theft accounted for most of the decrease in property crime. ************************************************************ *************** HIGHLIGHTS ************** Violent crime *************** * No statistically significant change occurred in the rate of violent crime from 2014 (20.1 victimizations per 1,000) to 2015 (18.6 per 1,000). * No statistically significant change was detected in the percentage of violent crime reported to police from 2014 (46%) to 2015 (47%). * No measureable change was detected in the percentage of violent crime victimizations in which victim services were received from 2014 (10.5%) to 2015 (9.1%). Property crime *************** * The rate of property crime decreased from 118.1 victimizations per 1,000 households in 2014 to 110.7 per 1,000 in 2015. Prevalence of crime ********************* * In 2015, 0.98% of all persons age 12 or older (2.7 million persons) experienced at least one violent victimization. * The prevalence rate of violent victimization declined from 1.11% of all persons age 12 or older in 2014 to 0.98% in 2015. * In 2015, 7.60% of all households (10 million households) experienced one or more property victimizations. * The prevalence rate of property victimization declined from 7.99% of all households in 2014 to 7.60% in 2015. ************************************************************ ********************************************** No change was detected in the rate of serious violent crime from 2014 to 2015 ********************************************** There was no statistically significant change in the rate of serious violent crime, defined as rape or sexual assault, robbery, and aggravated assault, from 2014 (7.7 per 1,000) to 2015 (6.8 per 1,000) (table 1). The rate of aggravated assault had a decline (90% confidence level), from 4.1 victimizations per 1,000 persons in 2014 to 3.0 per 1,000 in 2015. During the same period, the rate of rape or sexual assault increased (90% confidence level), from 1.1 victimizations per 1,000 persons in 2014 to 1.6 per 1,000 in 2015 (see NCVS measurement of rape and sexual assault in Methodology). No measurable change was detected in the rate of simple assault from 2014 (12.4 per 1,000) to 2015 (11.8 per 1,000). ********************************************** No change was detected in the rate of intimate partner violence from 2014 to 2015 ********************************************** The rate of domestic violence, which includes crime committed by intimate partners and family members, was flat from 2014 to 2015. No measurable change was detected from 2014 to 2015 in the rate of intimate partner violence (3.0 per 1,000), which includes victimizations committed by current or former spouses, boyfriends, or girlfriends. However, the number of victimizations committed by an intimate partner increased (90% confidence level) from 2014 to 2015. The rate of serious violent crime involving weapons had a decline (90% confidence level) from 2014 (4.9 per 1,000) to 2015 (3.6 per 1,000). During the same period, the number of serious violent victimizations committed by a stranger decreased (90% confidence level). No statistically significant difference was found in the rate of serious violent crime resulting in physical injury to the victim from 2014 to 2015 (2.4 per 1,000). ********************************************** Firearm violence declined from 1993 to 2015 ********************************************** From 1993 to 2015, the rate of nonfatal firearm violence declined from 7.3 to 1.1 victimizations per 1,000 persons age 12 or older (figure 2). The majority of the decline in firearm violence occurred between 1994 and 1999. The rate then fluctuated between 1.1 and 2.7 per 1,000 through 2015. An estimated 284,910 nonfatal firearm victimizations occurred in 2015 (appendix table 4). In 2015, 76% of all serious violent crimes that involved a firearm were reported to police. ************************************************************ ******************************************** The National Crime Victimization Survey ******************************************** The National Crime Victimization Survey (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. The NCVS was designed to complement official police statistics, such as the FBI’s Uniform Crime Reporting (UCR) program. The UCR includes only crimes reported to police while the NCVS includes crimes that were reported and not reported to police, or the “dark figure of crime.” See page 4 for more information on the differences between the NCVS and UCR. Initial NCVS interviews are conducted in person with subsequent interviews conducted either in person or by phone. In 2015, the response rate was 82% for households and 86% for eligible persons. The NCVS produces national rates and levels of violent and property victimization, as well as information on the characteristics of crimes and victims and the consequences of victimization. Because the NCVS is based on interviews with victims, it cannot measure homicide. The NCVS measures the violent crimes of rape or sexual assault, robbery, aggravated assault, and simple assault. The NCVS classifies rape, sexual assault, robbery, and aggravated assault as serious violent crimes. Property crimes include household burglary, motor vehicle theft, and theft. The survey also measures personal larceny, which includes pickpocketing and purse snatching. For additional estimates not included in this report, see the NCVS Victimization Analysis Tool (NVAT) on the BJS website. Victimization is the basic unit of analysis used throughout most of this report. A victimization is a crime as it affects one person or household. For personal crimes, the number of victimizations is equal to the number of victims present during a criminal incident. The number of victimizations may be greater than the number of incidents because more than one person may be victimized during an incident. Each crime against a household is counted as having a single victim--the affected household. The victimization rate is a measure of the occurrence of victimizations among a specified population group. For personal crimes, the victimization rate is based on the number of victimizations per 1,000 residents age 12 or older. For household crimes, the victimization rate is calculated using the number of incidents per 1,000 households. Estimates are presented for 2014 and 2015. ************************************************************ ************************************************************ ******************************************** From 2014 to 2015, the UCR reported that the number of serious violent crimes increased 4% while NCVS estimates were flat ******************************************** For 2015, findings from the FBI’s Uniform Crime Reporting (UCR) program showed a 4% increase in the number of serious violent crimes, compared to 2014 (table 2). The Bureau of Justice Statistics’ (BJS) National Crime Victimization Survey (NCVS) did not show a statistically significant change in the number of serious violent victimizations during this same period. Because the NCVS and UCR measure an overlapping, but not identical, set of offenses and use different methodologies, congruity between the estimates is not expected. Throughout the 40-year history of the NCVS, both programs have generally demonstrated similar year-to-year increases or decreases in the levels of overall violent and property crimes. The UCR measures the violent crimes of murder and nonnegligent manslaughter, forcible rape, robbery, and aggravated assault. For property crime, the UCR measures burglary, larceny-theft, and motor vehicle theft. The UCR measures crimes known to law enforcement, occurring against both persons and businesses. The FBI obtains data on crimes from law enforcement agencies, while the NCVS collects data through interviews with victims. Additional information about the differences between the two programs can be found in The Nation’s Two Crime Measures (NCJ 246832, BJS web, September 2014). Significant methodological and definitional differences exist between the NCVS and UCR: ** The NCVS obtains estimates of crimes both reported and not reported to police, while the UCR collects data on crimes known to and recorded by law enforcement. ** The UCR includes homicide and commercial crimes, while the NCVS excludes these crime types. ** The UCR excludes simple assault and sexual assault, which are included in the NCVS. *** Footnote 1 Simple assaults include attacks or attempted attacks without a weapon resulting in either no injury or minor injury. Sexual assaults include attacks or attempted attacks generally involving unwanted sexual contact between the victim and offender that may or may not involve force.*** ** The NCVS estimates are based on data from a nationally representative sample of U.S. households. The UCR percentage changes are based on counts of offenses reported by a large sample of law enforcement agencies. ** The NCVS excludes crimes against children age 11 or younger, persons in institutions (e.g., nursing homes and correctional institutions), and may exclude highly mobile populations and persons who are homeless. Victimizations against these persons are included in the UCR. Given these differences, the two measures of crime should complement each other and provide a more comprehensive picture of crime in the United States. From 2014 to 2015, the UCR showed increases in all types of serious violent crimes known to law enforcement. The NCVS showed an increase (90% confidence level) in the number of rape or sexual assaults from 2014 to 2015. However, no other NCVS violent crime types increased during this time. From 2014 to 2015, the UCR showed a decline in overall property crime and the NCVS showed a decline (90% confidence level). Data from both the NCVS and UCR showed a decline in the number of household burglaries that were reported to the police from 2014 to 2015. Both the UCR and total NCVS estimates showed an increase in motor vehicle theft. However, the apparent increase was not statistically significant for the NCVS. ************************************************************ ******************************************** Property crime declined from 2014 to 2015 ******************************************** Similar to the trend in the rate of violent crime, the property crime rate declined over the longer term. From 1993 to 2015, the rate of property crime declined from 351.8 to 110.7 victimizations per 1,000 households (figure 3). The majority of this decline occurred from 1993 to 2001. Following the decline from 2013 to 2014, the rate of property crime victimization decreased again from 2014 (118.1 victimizations per 1,000 households) to 2015 (110.7 per 1,000) (table 3). This recent decline was driven primarily by a decrease in theft. The rate of theft declined from 90.8 victimizations per 1,000 households in 2014 to 84.4 per 1,000 in 2015. From 2014 to 2015, no statistically significant change was observed in the rate of burglary or motor vehicle theft. ******************************************** No change was detected in the percentage of violent victimizations reported to police from 1993 to 2015 ******************************************** The NCVS allows for examination of crimes reported and not reported to police. Victims may not report the victimization for a variety of reasons, including fear of reprisal or getting the offender in trouble, believing that police would not or could not do anything to help, and believing the crime to be a personal issue or too trivial to report. Police notification can come from the victim, a third party (including witnesses, other victims, household members, or other officials, such as school officials or workplace managers), or police at the scene of the incident. Police notification may occur during or immediately following a criminal incident or at a later date. The term “police” includes municipal police departments, sheriffs’ offices, or other state or local law enforcement agencies. The percentage of violent and serious violent victimizations reported to police was generally stable over the 23 years from 1993 to 2015. There was no statistically significant change in the percentage of violent victimizations reported to police from 1993 (42%) to 2015 (47%)(figure 4). There was also no statistically significant change in the percentage of serious violent victimizations reported to police during that same period. More than half of serious violent victimizations were reported to police in 1993 (51%) and 2015 (55%). The percentage of property victimizations reported to police increased from 1993 (32%) to 2015 (35%). The majority of the increase occurred from 1993 to 2002. From 2003 to 2015, the percentage fluctuated from 34% to 40%. ******************************************** In 2015, 47% of violent victimizations were reported to police ******************************************** From 2014 to 2015, no statistically significant change was detected in the percentage of violent and serious violent victimizations reported to police (table 4). In 2015, a greater percentage of robberies (62%) and aggravated assaults (62%) were reported to police than simple assaults (42%) and rape or sexual assaults (32%). The percentage of stranger violence reported to police (42%) was lower than the percentage of domestic violence (58%) and lower (90% confidence level) than intimate partner violence (54%) reported to police in 2015. From 2014 to 2015, the percentage of total property victimizations reported to police decreased from 37% to 35%. The percentage of household burglaries reported to police also decreased from 60% in 2014 to 51% in 2015. The percentage of motor vehicle thefts reported to police decreased from 83% to 69% during the same period. There was no statistically significant change in the percentage of thefts reported to police from 2014 to 2015. ******************************************** Rates of property crime reported to police declined from 2014 to 2015 ******************************************** From 2014 to 2015, the rate of stranger violence reported to police had a decline (90% confidence level) from 4.0 victimizations per 1,000 persons to 2.8 per 1,000 (table 5). The rate of serious stranger violence reported to police declined from 2.3 victimizations per 1,000 persons in 2014 to 1.4 per 1,000 in 2015. There were no measurable differences from 2014 to 2015 in rates of overall violent crime or serious violent crime reported to police. In comparison, overall rates of property crime reported to police declined from 2014 to 2015. The overall rate of property crime reported to police decreased from 43.7 victimizations per 1,000 households in 2014 to 38.3 per 1,000 in 2015. This was driven primarily by a decline in household burglary reported to police (13.9 victimizations per 1,000 households in 2014 to 11.2 per 1,000 in 2015). The rate of theft victimizations reported to police also declined (90% confidence level) from 2014 (26.4 victimizations per 1,000 households) to 2015 (24.1 per 1,000). The rate of unreported property crime remained flat from 2014 to 2015. The rates of household burglary and motor vehicle theft not reported to police increased from 2014 to 2015. The rate of household burglary not reported to police increased from 8.8 victimizations per 1,000 households in 2014 to 10.5 per 1,000 in 2015. The rate of motor vehicle theft not reported to police increased from 0.7 victimizations per 1,000 households in 2014 to 1.3 per 1,000 in 2015. The rate of unreported theft victimizations had a decline (90% confidence level) from 63.3 victimizations per 1,000 households in 2014 to 59.5 per 1,000 in 2015. ******************************************** From 2014 to 2015, no change was detected in the percentage of violent victimizations in which assistance from a victim service agency was received ******************************************** Victim service agencies are publicly or privately funded organizations that provide victims with support and services to aid their physical and emotional recovery, offer protection from future victimizations, guide them through the criminal justice system process, and assist them in obtaining restitution. Victims may not receive services because they do not seek or ask for assistance, do not qualify, or services may not be available. From 2014 to 2015, no significant change was detected in the overall percentage of violent crime victimizations where assistance from a victim service agency was received (9.1%) (table 6). The percentage of simple assault victimizations in which assistance from a victim service agency was received declined (90% confidence level) from 9.5% in 2014 to 6.0% in 2015. The percentage of intimate partner violence where assistance was received from a victim service agency also had a decline (90% confidence level) from 28.2% to 18.3%. The only increase from 2014 to 2015 in the percentage of violent crime victimizations where assistance was received from a victim service agency was for violent crime victimizations in which a weapon was involved. The percentage of these victimizations increased from 7.2% in 2014 to 15.0% in 2015. ******************************************** The rate of violent victimization committed against males decreased from 2014 to 2015 ******************************************** The rate of violent and serious violent victimization committed against males decreased from 2014 to 2015 (table 7). Among males, the rate of violent victimization decreased from 21.1 victimizations per 1,000 males in 2014 to 15.9 per 1,000 in 2015. With this decline, the violent victimization rate for males dropped below that for females (21.1 per 1,000) in 2015. The rate of serious violent victimization for males decreased from 8.3 per 1,000 in 2014 to 5.4 per 1,000 in 2015. No statistically significant difference was detected in the rate of violent or serious violent victimizations committed against females from 2014 to 2015. From 2014 to 2015, the violent victimization rate for persons ages 25 to 34 declined (90% confidence level) from 28.5 victimizations per 1,000 persons to 21.8 per 1,000. The violent victimization rate for persons age 65 or older had an increase (90% confidence level) from 3.1 victimizations per 1,000 persons in 2014 to 5.2 per 1,000 in 2015. No age groups had a measurable change in rates of serious violent victimization from 2014 to 2015. In 2015, persons age 65 or older had a lower rate of violent victimization (5.2 per 1,000) than persons in any other age group studied. From 2014 to 2015, there were no statistically significant differences in the rates of violent or serious violent crime by victim race or Hispanic origin, marital status, or household income. ******************************************** Property crime declined in urban areas and the South from 2014 to 2015 ******************************************** From 2014 to 2015, there were no significant differences in rates of violence or serious violence by region (table 8). There were also no significant differences detected in rates of violence across any of the four regions in 2015. The rate of serious violence was higher in the West (8.8 victimizations per 1,000) than the Northeast (5.1 per 1,000) and higher (90% confidence level) than the South (5.8 per 1,000) in 2015. Rates of violence and serious violence were flat across urban, suburban, and rural areas from 2014 to 2015. In 2015, the rate of violent crime in urban areas (22.7 victimizations per 1,000 persons) was higher than the rate in suburban (17.3 per 1,000) and rural (14.0 per 1,000) areas. The rate of serious violence was higher in urban areas (8.6 per 1,000) than the rate in rural areas (4.2 per 1,000) in 2015. There was no statistically significant change in the rates of property crime in the Northeast, Midwest, and West from 2014 to 2015. In the South, the property crime rate declined from 116.2 victimizations per 1,000 households in 2014 to 107.6 per 1,000 in 2015. As in 2014, property crime rates were highest in the West (144.7 victimizations per 1,000 households) and lowest in the Northeast (81.6 per 1,000) in 2015. Property crime rates declined in urban areas from 2014 to 2015, but did not change significantly in suburban and rural areas. The rate of property crime in urban areas declined from 148.8 victimizations per 1,000 households in 2014 to 135.4 per 1,000 in 2015. In 2015, urban areas (135.4 per 1,000) had a higher rate of property crime victimization than suburban (98.4 per 1,000) and rural (95.7 per 1,000) areas. ************************************************************ *************************** Prevalence of crime *************************** Annual estimates of a population’s risk for criminal victimization can be examined using victimization rates or prevalence rates. Historically, the Bureau of Justice Statistics (BJS) reports that use the National Crime Victimization Survey (NCVS) data rely on victimization rates, which measure the extent to which victimizations occur in a specified population during a specific time. Victimization rates are used throughout this report. For crimes affecting persons, NCVS victimization rates are estimated by dividing the number of victimizations that occur during a specified time (T) by the population at risk for those victimizations and multiplying the rate by 1,000. Victimization rate T = Number of victimizations experienced by a specified population T _________________________________________ x 1,000 Number of persons in the specified population T Prevalence rates also describe the level of victimization but are based on the number of unique persons (or households) in the population who experienced at least one victimization during a specified time. The key distinction between a victimization rate and a prevalence rate is whether the numerator consists of the number of victimizations or the number of victims. For example, a person who experienced two robberies on separate occasions within the past year would be counted twice in the victimization rate but counted once in the prevalence rate. Prevalence rates are estimated by dividing the number of victims in the specified population by the total number of persons in the population and multiplying the rate by 100. This is the percentage of the population victimized at least once in a given period. Prevalence rate T = Number of victims in a specified population T ___________________________________ x 100 Number of persons in the specified population T Victimization and prevalence rates may also be produced for household crimes, such as burglary. In these instances, the numerators and denominators are adjusted to reflect households rather than persons. To better understand the percentage of the population that is victimized at least once in a given period, prevalence rates are presented by type of crime and certain demographic characteristics. (For further information about measuring prevalence in the NCVS, see Measuring the Prevalence of Crime with the National Crime Victimization Survey, NCJ 241656, BJS web, September 2013). ******************************************** In 2015, an estimated 1% of all persons age 12 or older experienced violence ******************************************** In 2015, 0.98% of all persons age 12 or older (2.7 million persons) experienced at least one violent victimization (table 9). The prevalence rate of violent victimization declined from 1.11% in 2014 to 0.98% in 2015. During the same period, an estimated 0.41% of all persons age 12 or older (1.1 million persons) experienced at least one serious violent victimization (rape or sexual assault, robbery, and aggravated assault). No measurable change was detected in the prevalence rate of serious violent victimization from 2014 to 2015. During the same period, the prevalence rate of aggravated assault declined (90% confidence level) from an estimated 0.26% to 0.21%. The prevalence rate of domestic violence had a decline (90% confidence level) from 2014 (0.22%) to 2015 (0.18%). No measurable change occurred in the prevalence rate of intimate partner violence from 2014 to 2015 (0.12%). The prevalence of serious violence committed by strangers declined from 2014 (0.23%) to 2015 (0.18%). During the same period, the prevalence rate of serious violence involving weapons declined from 0.31% to 0.24%. In 2015, 7.60% of all households (10.0 million households) experienced one or more property victimization. The prevalence rate of property victimization declined from 7.99% in 2014 to 7.60% in 2015. During the same period, the prevalence of theft also declined (6.41% to 6.02%). No measurable change occurred in the prevalence rates of burglary and motor vehicle theft from 2014 to 2015. Similar to the property victimization rate, the decline in the prevalence rate of theft accounted for the majority of the decline in the prevalence rate of property victimization. ******************************************** Prevalence of violent crime among males declined from 2014 to 2015 ******************************************** In 2015, 0.94% of all males age 12 or older (1.2 million males) and 1.03% of all females age 12 or older (1.4 million females) experienced one or more violent victimizations (table 10). There was no significant difference in the prevalence rates for males and females in 2015. The prevalence rate for males declined from 2014 (1.15%) to 2015 (0.94%), while no measureable change was detected in the prevalence rate for females in that timeframe. No measurable change occurred in the prevalence rates of violent crime for non-Hispanic whites, non-Hispanic blacks, or Hispanics from 2014 to 2015. While there were more than four times more white victims (1.7 million) than black victims (394,770) in 2015, blacks (1.19%) had a higher prevalence rate (90% confidence level) than whites (0.96%). Similar to 2014, there was no significant difference in Hispanic (0.93%) and white (0.96%) prevalence rate in 2015. The prevalence of violent crime declined for persons ages 25 to 34 from 2014 (1.51%) to 2015 (1.09%). No measurable change was detected in the prevalence rates for all other age groups studied. In 2015, persons ages 12 to 17 (1.64%) and 18 to 24 (1.46%) had the highest prevalence of violence of all age groups. Persons age 65 or older had the lowest prevalence rate with 0.29% of the population experiencing one or more violent crimes. For married persons, the prevalence of violence declined (90% confidence level) from 2014 (0.63%) to 2015 (0.54%). The prevalence of violence for persons who were separated declined from 2.99% in 2014 to 1.65% in 2015. Persons who were never married had a higher prevalence rate of violence (1.44%) than persons who were married (0.54%) or widowed (0.62%) in 2015. ************************************************************ ************* Methodology ************* Survey coverage ***************** The National Crime Victimization Survey (NCVS) is an annual data collection conducted by the U.S. Census Bureau for the Bureau of Justice Statistics (BJS). The NCVS is a self-report survey in which interviewed persons are asked about the number and characteristics of victimizations experienced during the prior 6 months. The NCVS collects information on nonfatal personal crimes (rape or sexual assault, robbery, aggravated and simple assault, and personal larceny) and household property crimes (burglary, motor vehicle theft, and other theft) both reported and not reported to police. In addition to providing annual level and change estimates on criminal victimization, the NCVS is the primary source of information on the nature of criminal victimization incidents. Survey respondents provide information about themselves (e.g., age, sex, race and Hispanic origin, marital status, education level, and income) and whether they experienced a victimization. For each victimization incident, the NCVS collects information about the offender (e.g., age, race and Hispanic origin, sex, and victim-offender relationship), characteristics of the crime (including time and place of occurrence, use of weapons, nature of injury, and economic consequences), whether the crime was reported to police, reasons the crime was or was not reported, and victim experiences with the criminal justice system. The NCVS is administered to persons age 12 or older from a nationally representative sample of households in the United States. The NCVS defines a household as a group of persons who all reside at a sampled address. Persons are considered household members when the sampled address is their usual place of residence at the time of the interview and when they have no usual place of residence elsewhere. Once selected, households remain in the sample for 3 years, and eligible persons in these households are interviewed every 6 months either in person or over the phone for a total of seven interviews. All first interviews are conducted in person with subsequent interviews conducted either in person or by phone. New households rotate into the sample on an ongoing basis to replace outgoing households that have been in the sample for the 3-year period. The sample includes persons living in group quarters, such as dormitories, rooming houses, and religious group dwellings, and excludes persons living in military barracks and institutional settings such as correctional or hospital facilities, and persons who are homeless. Nonresponse and weighting adjustments **************************************** In 2015, 95,760 households and 163,880 persons age 12 or older were interviewed for the NCVS. Each household was interviewed twice during the year. The response rate was 82% for households and 86% for eligible persons. Victimizations that occurred outside of the United States were excluded from this report. In 2015, less than 1% of the unweighted victimizations occurred outside of the United States and were excluded from the analyses. Estimates in this report use data from the 1993 to 2015 NCVS data files, weighted to produce annual estimates of victimization for persons age 12 or older living in U.S. households. Because the NCVS relies on a sample rather than a census of the entire U.S. population, weights are designed to inflate sample point estimates to known population totals and to compensate for survey nonresponse and other aspects of the sample design. The NCVS data files include both person and household weights. Person weights provide an estimate of the population represented by each person in the sample. Household weights provide an estimate of the U.S. household population represented by each household in the sample. After proper adjustment, both household and person weights are also typically used to form the denominator in calculations of crime rates. Victimization weights used in this analysis account for the number of persons present during an incident and for high frequency repeat victimizations (i.e., series victimizations). Series victimizations are similar in type but occur with such frequency that a victim is unable to recall each individual event or describe each event in detail. Survey procedures allow NCVS interviewers to identify and classify these similar victimizations as series victimizations and to collect detailed information on only the most recent incident in the series. The weight counts series incidents as the actual number of incidents reported by the victim, up to a maximum of 10 incidents. Including series victimizations in national rates results in large increases in the level of violent victimization. However, trends in violent crime are generally similar, regardless of whether series victimizations are included. In 2015, series incidents accounted for about 1% of all victimizations and 4% of all violent victimizations. Weighting series incidents as the number of incidents up to a maximum of 10 incidents produces more reliable estimates of crime levels, while the cap at 10 minimizes the effect of extreme outliers on rates. Additional information on the series enumeration is detailed in the report Methods for Counting High-Frequency Repeat Victimizations in the National Crime Victimization Survey (NCJ 237308, BJS web, April 2012). Standard error computations ****************************** When national estimates are derived from a sample, as with the NCVS, caution must be used when comparing one estimate to another estimate or when comparing estimates over time. Although one estimate may be larger than another, estimates based on a sample have some degree of sampling error. The sampling error of an estimate depends on several factors, including the amount of variation in the responses and the size of the sample. When the sampling error around an estimate is taken into account, the estimates that appear different may not be statistically different. One measure of the sampling error associated with an estimate is the standard error. The standard error can vary from one estimate to the next. Generally, an estimate with a small standard error provides a more reliable approximation of the true value than an estimate with a large standard error. Estimates with relatively large standard errors are associated with less precision and reliability and should be interpreted with caution. To generate standard errors around numbers and estimates from the NCVS, the Census Bureau produced generalized variance function (GVF) parameters for BJS. The GVFs take into account aspects of the NCVS complex sample design and represent the curve fitted to a selection of individual standard errors based on the Jackknife Repeated Replication technique. The GVF parameters were used to generate standard errors for each point estimate (e.g., counts, percentages, and rates) in this report. BJS conducted tests to determine whether differences in estimated numbers, percentages, and rates in this report were statistically significant once sampling error was taken into account. Using statistical programs developed specifically for the NCVS, all comparisons in the text were tested for significance. The primary test procedure was the Student’s t-statistic, which tests the difference between two sample estimates. Unless otherwise noted, the findings described in this report as higher, lower, or different passed a test at the 0.05 level of statistical significance (95% confidence level). Findings that passed a test at the 0.10 level of significance are noted as such in the text, i.e. (90% confidence level). Caution is required when comparing estimates not explicitly discussed in this report. Data users can use the estimates and the standard errors of the estimates provided in this report to generate a confidence interval around the estimate as a measure of the margin of error. The following example illustrates how standard errors can be used to generate confidence intervals: According to the NCVS, in 2015, the violent victimization rate among persons age 12 or older was 18.6 per 1,000 persons (see table 1). Using the GVFs, it was determined that the estimated victimization rate has a standard error of 1.16 (see appendix table 2). A confidence interval around the estimate was generated by multiplying the standard errors by ±1.96 (the t- score of a normal, two-tailed distribution that excludes 2.5% at either end of the distribution). Therefore, the 95% confidence interval around the 18.6 estimate from 2015 is 18.6 ± (1.16 × 1.96) or (16.31 to 20.85). In others words, if different samples using the same procedures were taken from the U.S. population in 2015, 95% of the time the violent victimization rate would fall between 16.3 and 20.8 per 1,000 persons. In this report, BJS also calculated a coefficient of variation (CV) for all estimates, representing the ratio of the standard error to the estimate. CVs provide a measure of reliability and a means for comparing the precision of estimates across measures with differing levels or metrics. NCVS measurement of rape and sexual assault ********************************************* Definition of rape and sexual assault *************************************** The measurement of rape and sexual assault presents many challenges. Victims may not be willing to reveal or share their experiences with an interviewer. The level and type of sexual violence reported by victims is sensitive to a variety of factors related to the interview process, including how items are worded, what definitions are used, and the data collection mode. In addition, the legal definitions of rape and sexual assault vary across jurisdictions. For the NCVS, survey respondents are asked to respond to a series of questions about the nature and characteristics of their victimization. The NCVS classifies victimizations as rape or sexual assault even if other crimes, such as robbery or assault, occurred at the same time. Then, the NCVS uses the following rape and sexual assault definitions: Rape is the unlawful penetration of a person against the will of the victim, with use or threatened use of force, or attempting such an act. Rape includes psychological coercion and physical force, and forced sexual intercourse means vaginal, anal, or oral penetration by the offender. Rape also includes incidents where penetration is from a foreign object (e.g., a bottle), victimizations against male and female victims, and both heterosexual and homosexual rape. Attempted rape includes verbal threats of rape. Sexual assault is defined across a wide range of victimizations, separate from rape or attempted rape. These crimes include attacks or attempted attacks generally involving unwanted sexual contact between a victim and offender. Sexual assault may or may not involve force and includes grabbing or fondling. While the change in the rape or sexual assault rate from 2014 to 2015 is significantly different at the 90% confidence level, care should be taken in interpreting this change because the estimates of rape or sexual assault are based on a small number of cases reported to the survey. Therefore, small absolute changes and fluctuations in the rates of victimization can result in larger year-to-year change estimates. For 2015, the estimate of rape or sexual assault is based on 103 unweighted cases, compared to 69 unweighted cases in 2014 (table 11). From 2006 to 2015, 28% of NCVS rape and sexual assault victimizations were classified as completed rape (table 12). Attempted rape or other sexual assault accounted for nearly 50% of rape or sexual assault victimizations. About 1 in 5 (17%) were verbal threats of rape or sexual assault. Efforts to improve the measurement of rape and sexual assault **************************************** Over the past several decades, a number of other surveys have also been used to study rape and sexual assault. However, challenges exist in the collection of self-report data on rape and sexual assault from the general population. BJS estimates of rape and sexual assault from the NCVS have typically been lower than estimates derived from other federal and private surveys. Some of the differences in these estimates result from varying definitions of rape and sexual assault. The NCVS definition is shaped from a criminal justice perspective and includes threatened, attempted, and completed rape and sexual assault against males and females. In addition to differences in defining rape and sexual assault victimization, the methodology used to elicit reports of these events can differ dramatically and produce very different estimates of the incidence of these crimes. For further information, see Rape and Sexual Assault Victimization Among College-Age Females, 1995–2013 (NCJ 248471, BJS web, December 2014). BJS has initiated projects to identify, develop, and test the best methods for collecting self-report data on rape and sexual assault. In June 2011, BJS charged an expert panel from the National Research Council’s Committee on National Statistics (CNSTAT) to examine conceptual and methodological issues surrounding survey statistics on rape and sexual assault and to recommend to BJS the best methods for obtaining such statistics on an ongoing basis. In September 2011, BJS made a competitive award to Westat, Inc., to develop and test two different survey designs for collecting self-report data on rape and sexual assault. One is an optimal design identified by the CNSTAT panel and the other is similar to designs used in the public health approach for measuring rape and sexual assault. Estimates from these two designs will be compared to data from the NCVS. Additionally, BJS conducted the Campus Climate Survey Validation Study (CCSVS) in 2015 (See Campus Climate Survey Validation Study Final Technical Report, NCJ 249545, BJS web, January 2016). The study aimed to develop and test a survey instrument and methodology for efficiently collecting valid school-level data on campus climate and sexual violence. More information on BJS’s active research program on the collection of rape and sexual assault data can be found on the BJS website. Methodological changes to the NCVS in 2006 ******************************************** Methodological changes implemented in 2006 may have affected the crime estimates for that year to such an extent that they are not comparable to estimates from other years. Previous Criminal Victimization reports have included a 10-year comparison, in addition to the annual change. However, because the 10-year comparison for this year would be 2006, this report does not include a 10-year comparison. Evaluation of 2007 and later data from the NCVS conducted by BJS and the Census Bureau found a high degree of confidence that estimates for 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, and 2015 are consistent with and comparable to estimates for 2005 and previous years. The reports are available on the BJS website: ** Criminal Victimization, 2006 (NCJ 219413, December 2007) ** Criminal Victimization, 2007 (NCJ 224390, December 2008) ** Criminal Victimization, 2008 (NCJ 227777, September 2009) ** Criminal Victimization, 2009 (NCJ 231327, October 2010) ** Criminal Victimization, 2010 (NCJ 235508, September 2011) ** Criminal Victimization, 2011 (NCJ 239437, October 2012) ** Criminal Victimization, 2012 (NCJ 243389, October 2013) ** Criminal Victimization, 2013 (NCJ 247648, September 2014) ** Criminal Victimization, 2014 (NCJ 248973, August 2015) Imputation of household income ******************************** The NCVS asks the reference person of a household about the household’s income level during the first interview and every odd-numbered interview after that. When household income is not asked, the income from the previous interview is carried forward. When included, respondents are asked to choose a household income from 1 of 14 categories (the highest category is an income of $75,000 or more). Respondents are asked to indicate a range for their income rather than a specific amount. These procedures are intended to minimize the burden and intrusiveness respondents may feel about providing their income. However, even with these procedures, an average of 32% of households from 2014 to 2015 did not provide a household income when asked. To effectively analyze criminal victimization, household income needed to be imputed when a household did not provide a value. As detailed in the report, Imputing NCVS Income Data (NCJ 248563, BJS web, January 2015), a household’s missing income category was imputed using a hot deck approach that relied on one of two methods, depending on the household’s previous income response status. When a household provided a household income category in a previous interview, the previous income value was used to predict the household’s current income level. When a household had never provided a household income value, the distribution of household income among respondents from the interview period of interest was used to predict the household’s current income level. Because these procedures require linking households across their interview waves, the imputation process could only be implemented starting in 2008. In 2006, the scrambled control numbers the U.S. Census Bureau used to identify households were changed to account for the phase-in of the 2000 Census primary sampling units. Therefore, 2007 was used as a base year from which households in existing sample rotation groups could be linked in 2008 and beyond. ************************************************************ The Bureau of Justice Statistics of the U.S. Department of Justice is the principal federal agency responsible for measuring crime, criminal victimization, criminal offenders, victims of crime, correlates of crime, and the operation of criminal and civil justice systems at the federal, state, tribal, and local levels. BJS collects, analyzes, and disseminates reliable and valid statistics on crime and justice systems in the United States, supports improvements to state and local criminal justice information systems, and participates with national and international organizations to develop and recommend national standards for justice statistics. Jeri M. Mulrow is acting director. This report was written by Jennifer L. Truman and Rachel E. Morgan. Shannan Catalano verified the report. Monika Potemra and Jill Thomas edited the report. Tina Dorsey and Barbara Quinn produced the report. October 2016, NCJ 250180 ************************************************************ ************************************************** Office of Justice Programs Innovation * Partnerships * Safer Neighborhoods www.ojp.usdoj.gov ************************************************** ********************** 10/11/2016/JER/11:25am **********************