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Daily Driver Advocate
Verified June 2026

Independent Research Project Data Source Card

FARS2024NationalAuxiliaryCSV.zip

A source card for the official NHTSA 2024 FARS national auxiliary CSV package. This supplemental release extends the core FARS national CSV with multiple imputation tables and additional analytical variables — primarily for estimating crash factors that carry high rates of unknown values in the raw data, such as blood alcohol concentration and travel speed.1,2,3,4

Official Source

Download from NHTSA rather than a third-party mirror. Use alongside FARS2024NationalCSV.zip — this package is supplemental, not standalone.

Download from NHTSA

File Identity

FARS2024NationalAuxiliaryCSV.zip is the 2024 national auxiliary CSV package for NHTSA's Fatality Analysis Reporting System. FARS is a census of fatal motor vehicle traffic crashes in the United States. The auxiliary package contains supplemental analytical tables — chiefly multiple imputation (MI) data files — that extend the core crash, vehicle, and person tables found in FARS2024NationalCSV.zip.1,2,3

Researchers use the auxiliary package when they need nationally representative estimates for variables that the raw FARS records frequently code as unknown. NHTSA's multiple imputation methodology statistically fills those gaps using models calibrated to the records where complete data is available.1,4

Official file name
FARS2024NationalAuxiliaryCSV.zip
Issuing agency
NHTSA / U.S. Department of Transportation
Coverage year
2024
Format
ZIP package containing CSV tables
Package type
Supplemental / auxiliary
Companion file
FARS2024NationalCSV.zip

What the Package Contains

The auxiliary ZIP contains CSV tables that extend the main FARS national package. The core content is the set of Multiple Imputation (MI) files NHTSA generates to address systematic data gaps in raw crash reports. Each MI file corresponds to a level of the FARS hierarchy — accident, driver/accident, and person — and provides multiply-imputed estimates alongside the original coded values.3,4

Table / file typePurpose and use
Multiple Imputation — Accident (MIACC)Provides statistically imputed values for accident-level variables that contain high rates of unknown or missing data, such as travel speed. Used to generate unbiased national estimates.
Multiple Imputation — Driver/Accident (MIDRVACC)Provides imputed values for driver-related accident variables, including estimated pre-crash speed and related driver-action fields where reporting is incomplete.
Multiple Imputation — Person (MIPER)Provides imputed values for person-level variables with high unknown rates, such as blood alcohol concentration (BAC) for drivers not tested. Essential for population-level impairment estimates.
Extended vehicle and person supplemental tablesAdditional analytical tables capturing supplemental coded variables for vehicles and persons that extend the detail available in the core FARS national CSV tables.

Consult the NHTSA FARS manuals for the exact file list and variable definitions.NHTSA may update which tables appear in the auxiliary versus the main package across annual releases. The FARS Analytical User's Manual (linked in the primary source directory) is the authoritative reference for the current file layout and imputation procedures.

How Daily Driver Advocate Uses It

Daily Driver Advocate references the NHTSA FARS auxiliary package as a companion to the main FARS CSV when a statistics page depends on imputed BAC or imputed speed estimates. NHTSA's published national drunk-driving fatality figures, for example, use the MI methodology to account for the fraction of drivers who were not tested. The auxiliary package is the documented data source behind those estimates.1,3,5

FARS2024NationalCSV.zip Source Card

The primary NHTSA fatal crash CSV package. Use together with the auxiliary package when imputed variables are required.

Open report

Fatal Crash Statistics & Facts

National factsheet with headline fatal crash and fatality figures derived from the 2024 FARS national CSV package.

Open report

Drunk Driving Statistics

Alcohol-impaired fatal-crash analysis that draws on FARS person-level BAC records and NHTSA imputed estimates.

Open report

Common Research Uses

The auxiliary package is most useful when raw FARS unknown-coded records are too numerous to ignore and a researcher needs nationally representative estimates rather than counts limited to the subset with complete data.1,4

Apply NHTSA multiple imputation methodology to estimate national statistics for variables with substantial missing data (BAC, travel speed).

Produce nationally representative drunk-driving and speeding estimates that account for the incomplete testing and reporting rates in raw FARS records.

Join imputed-variable tables to core FARS crash and person records for advanced regression and causal analysis.

Reproduce published NHTSA national traffic safety fact sheets, which often rely on imputed estimates rather than raw unknown-coded records.

Cross-validate raw FARS counts against MI-adjusted estimates to quantify reporting gaps in specific crash-factor categories.

Important Limitations

This page is a source card for an official federal dataset. It is not a government page, legal advice, crash investigation service, or substitute for the NHTSA file and manuals. Imputed values are statistical estimates, not confirmed measurements.

  • This package is supplemental — it must be used alongside FARS2024NationalCSV.zip, not as a standalone crash dataset.
  • Multiple imputation tables do not assign a single definitive value; they produce multiple plausible estimates intended for use with specialized statistical pooling procedures.
  • Imputed values are statistical estimates generated by NHTSA models, not confirmed measurements. They are appropriate for aggregate national estimates, not for case-level fact-finding.
  • FARS covers fatal crashes only. Neither the main nor the auxiliary package records injury-only or property-damage crashes.
  • A crash must involve a motor vehicle on a public trafficway and result in a death within 30 days to be included in any FARS file.
  • Consult the FARS Analytical User's Manual (linked in the primary source directory) for the exact variable definitions, coding notes, and imputation methodology used in each auxiliary table.

Suggested Citation

For the raw dataset, cite NHTSA as the issuing agency and link to the official file. When citing this explanatory card, cite Daily Driver Advocate as the independent research project that documented the source.

Raw Dataset Citation

National Highway Traffic Safety Administration. FARS2024NationalAuxiliaryCSV.zip. Fatality Analysis Reporting System, 2024 national auxiliary CSV package. https://static.nhtsa.gov/nhtsa/downloads/FARS/2024/National/FARS2024NationalAuxiliaryCSV.zip

Primary Source Directory

  1. Fatality Analysis Reporting System (FARS) overview
    Issuing authority: National Highway Traffic Safety Administration
    Direct URL: https://www.nhtsa.gov/research-data/fatality-analysis-reporting-system-fars
  2. FARS 2024 file download directory
    Issuing authority: National Highway Traffic Safety Administration
    Direct URL: https://www.nhtsa.gov/file-downloads?p=nhtsa/downloads/FARS/2024/
  3. FARS2024NationalAuxiliaryCSV.zip official download
    Issuing authority: National Highway Traffic Safety Administration
    Direct URL: https://static.nhtsa.gov/nhtsa/downloads/FARS/2024/National/FARS2024NationalAuxiliaryCSV.zip
  4. Links for FARS manuals (coding and analytical guides)
    Issuing authority: National Highway Traffic Safety Administration
    Direct URL: https://static.nhtsa.gov/nhtsa/downloads/FARS/Links%20for%20FARS%20Manuals.pdf
  5. FARS2024NationalCSV.zip companion source card
    Issuing authority: Daily Driver Advocate
    Direct URL: https://dailydriveradvocate.com/safety-data/sources/fars2024nationalcsv-zip