California VMT Data

VMT across the U.S. and California is trending upward, undermining our policy goals around climate, equity, and safety. Before the Covid-19 pandemic, total and per-capita VMT was increasing, both in California and in the United States more broadly. While VMT decreased sharply during the pandemic, it has since rebounded with national VMT returning to pre-pandemic levels. California VMT diverged from national trends somewhat during this period, falling well below U.S. VMT during the height of the pandemic in 2020 and recovering more slowly afterwards, but it is trending upward again.

To meet the state's ambitious climate goals, daily per-capita VMT must reach 17.2 by 2045 (a 29% reduction from 2001 levels). While California may have lower per-capita VMT than the U.S., it is still far above the levels needed to reach that goal and is trending in the wrong direction. Caltrans and its partners are striving to improve these trends by working to provide better access to destinations for all modes.

Data sources:

• California Public Roads Data
• California Population Estimates
• USDOT Highway Statistics Series (2001 - 2022 national VMT data)
• December 2023 Traffic Volume Trends (2023 VMT national VMT data)
• U.S. Population Estimates
• California Air Resources Board 2022 Scoping Plan Appendix E

A note on VMT data:

This analysis utilizes state-level Highway Performance Monitoring System (HPMS) data and national-level Highway Statistics Series data, which is derived from state-level HPMS data. There are several known issues with these data sources, as discussed in CARB's 2022 SB 150 Report, Appendix A. For their analysis, CARB utilized a hybrid approach, combining HPMS data with regional vehicle registration and fuel sales data. While appropriate for state-level analysis, this methodology was not feasible as national-level datasets weren't readily available. With these limitations in mind, HPMS data is used here due to a lack of alternative data sources. If more reliable datasets become available, this analysis will be updated. It is important to note that while different VMT data sources provide different VMT estimates, the overall trends remain relatively consistent across analyses.