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Abstract
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In this annual report, Traffic Safety Facts 2020: A Compilation of Motor Vehicle Crash Data, the National Highway Traffic Safety Administration presents descriptive statistics about traffic crashes of all severities, from those that result in property damage to those that result in the loss of human life.
Information from three of NHTSA's primary data systems has been combined to create a single source for motor vehicle traffic crash statistics. The first data system, the Fatality Analysis Reporting System (FARS), is probably the better known of the three sources. Established in 1975, FARS contains data on the most severe traffic crashes, those in which someone was killed. The second source is the National Automotive Sampling System General Estimates System (NASS GES), which began operation in 1988 and ended in 2015. NASS GES contains data from a nationally representative sample of police-reported crashes of all severities, including those that resulted in death, injury, or property damage. The third source is the Crash Report Sampling System (CRSS), which replaced NASS GES in 2016. CRSS is the redesigned nationally representative sample of police-reported traffic crashes.
FARS, GES, and CRSS were designed and developed by NHTSA's National Center for Statistics and Analysis (NCSA) to provide an overall measure of highway safety, to help identify traffic safety problems, to suggest solutions, and to help provide an objective basis on which to evaluate the effectiveness of motor vehicle safety standards and highway safety initiatives. Data from these systems is used to answer requests for information from the international and national highway traffic safety communities, including State and local governments, the Congress, Federal agencies, research organizations, industry, the media, and the general public.
Fatal crash data from FARS and nonfatal crash data from GES and CRSS are presented in this report in five chapters. Chapter 1, "Trends," presents data from all years of FARS (1975 to 2020), GES (1988 to 2015), and CRSS (2016 to 2020). The remaining chapters present data only from 2020. Chapter 2, "Crashes," describes general characteristics of crashes, such as when and how often they occurred, where they occurred, and what happened during the crashes. Chapter 3, "Vehicles," concentrates on the types of vehicles involved in crashes and the damage to the vehicles. Chapter 4, "People," is the largest chapter of this report, with statistics about drivers, passengers, pedestrians, and pedalcyclists. The last chapter, "States," contains information about crashes for each State, the District of Columbia, and Puerto Rico. Terms used throughout the report are defined in the Glossary. Statistics describing fatal crashes or fatalities have been derived from FARS. Statistics describing injury or property-damage-only crashes have been derived from GES (or CRSS) and statistics describing nonfatal injuries have been derived from both FARS and GES (or CRSS). The reader should be aware that FARS numbers are actual counts of fatalities or fatal crashes, whereas GES and CRSS numbers are estimates of counts of crashes and people injured and are subject to sampling and non-sampling errors. (See Appendix C for more information on these errors.) To emphasize this difference, FARS numbers are not rounded, while GES and CRSS estimates have been rounded to the nearest thousand. As a result of the rounding, for some tables, the sum of the row or column entries may not equal the row or column total. In addition, percentages have been calculated prior to rounding. The reader may also notice that many tables have rows or footnotes for "unknowns" for FARS data, but not for GES or CRSS data. The reason for this difference is that almost all the GES or CRSS unknown data have been assigned values through complex statistical procedures. FARS unknown data, on the other hand, are not assigned values, with the exception of BAC test results. When the alcohol test results are unknown, BAC values in g/dL have been assigned to drivers and nonoccupants involved in fatal crashes, using a method of multiple imputation revised in 2001. More information on the multiple imputation method, including detailed tabulations of alcohol involvement in various categories (age, sex, time of day, etc.), is available in a NHTSA Technical Report, Transitioning to Multiple Imputation: A New Method to Estimate Missing Blood Alcohol Concentration (BAC) Values in FARS. |