Answers to Many of Your Questions

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For More Information

For more information, contact: 

David Schrank
(979) 317-2464
[email protected]

Bill Eisele
(979) 317-2461
[email protected]

  1. Can I download the report from the internet?
    Yes. Link to:
  2. What does “cost of congestion” mean?
    Value of extra travel time (which we call delay) and the extra fuel consumed by vehicles traveling at slower speeds. Travel time has a value of $23.12 per person-hour and $64.68 per truck-hour in 2022. Fuel cost per gallon is the average price for each state.
  3. What is the Travel Time Index?
    The ratio of the travel time during the peak period to the time required to make the same trip at free-flow speeds. A value of 1.30, for example, indicates a 20-minute free-flow trip requires 26 minutes during the peak period (20 minutes × 1.30 = 26 minutes). The Commuter Stress Index is the same as the Travel Time Index but is based only on peak direction travel only.
  4. What is the Planning Time Index (95th)?
    The PTI is a travel time reliability measure representing the total travel time that should be planned for a trip. Computed as the 95th percentile travel time divided by the free-flow travel time, it shows the amount of time that should be planned for a trip to be late for only one day a month. A PTI of 3.00 means that for a 20-minute trip in light traffic, 60 minutes should be planned. The PTI value represents the “worst trip of the month”. This measure resonates with individual commuters and truck drivers delivering goods – they need to allow more time for urgent trips.
  5. Where should I look for national data and trends?
    Look at the Summary Tables – National Congestion Levels and Trends.
  6. Where is the information about MY city?
    Here’s the link: There are multiple pages of trend data about your city. There is also a spreadsheet available for download with statistics for the 101 intensively studied areas as well as the remaining U.S. urban areas. Click on “Excel Spreadsheet” on this link:
  7. How did you pick the 101 intensively studied urban areas?
    We have all of the urban areas with more than 500,000 people. We have several smaller cities, mostly chosen by the previous report sponsors. This is not a representative list.
  8. Which one of these tables has the information that I need to know?
    We strongly suggest that you examine all the measures. The Delay per Auto Commuter, Cost per Auto Commuter, and Travel Time Index are estimates of the congestion effects on individuals. Total Delay or Total Cost identifies the size of the congestion problem in the urban area. The change in values over time indicates the rate of growth or decline.
  9. Where does my city rank?
    The city data tables show performance measure trends for several measures. Readers should compare ranking changes and performance measure values. In some performance measures a small change in the value may cause a significant change in rank from one year to the next. This is the case when there are several regions with nearly the same value (i.e., 15 hours is only 1 hour more than 14 hours). It is also important to look at trends. The multi-year performance measures are better indicators, in most cases, than any single year.
  10. What do you mean “There are several different rankings?”
    There are several congestion measures and each has a use and a significance. There is no single, best measure. There are rankings for most measures.
  11. How were 2022 traffic volumes generated?
    The 2022 traffic volumes were not available at the time of this report. The 2021 traffic volumes were used as the basis and adjustments were made to them based on traffic level factors from INRIX and other data sources.
  12. What are the titles of the researchers?
    David Schrank: Senior Research Scientist
    Luke Albert: Associate Research Engineer
    Kartik Jha: Assistant Research Scientist
    Bill Eisele: Senior Research Engineer