Data Updates in the NCST California Induced Travel Calculator 2022-2024
The California Induced Travel Calculator, published by the National Center for Sustainable Transportation (NCST) at UC Davis, has been updated with newer lane-mile and Vehicle Miles Traveled (VMT) data for the years 2022, 2023, and 2024. The NCST Calculator had previously used lane mileage data from the Highway Performance Monitoring System (HPMS) for baseline years 2016 through 2019.
This update will allow project teams to use more recent data to estimate project-specific induced VMT. This is important, as relevant Caltrans guidance – the Transportation Analysis Framework (TAF) – includes the California Induced Travel Calculator as one approach to estimate induced VMT for State Highway System capacity projects for California Environmental Quality Act (CEQA) analyses. During the preparation and circulation of the draft 2nd Edition TAF, a question was raised about plans to update the data used in the NCST Calculator. Caltrans noted that we would coordinate with UC Davis to assess the feasibility of incorporating newer data into future updates to the tool.
The calculator is available online at: https://travelcalculator.ncst.ucdavis.edu/
Proposed projects that have completed and received Caltrans approval for an induced VMT analysis have the option to revise the induced VMT analysis using year 2024 data, but they are not required to do so. Projects that have not yet completed an Induced VMT analysis must use the most recent year for which data is available. As of January 2026, the most recently available data is for year 2024.
For more information on the NCST California Induced Travel Calculator, see: