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1.    Caltrans Performance Measurement System (PeMS)

Traffic data collected from 40,000+ detectors across all major freeways in the state of California. Includes information on congestion, travel times, delays, lane closures, traffic census, etc.

As used in: Bento, Antonio, Kevin Roth and Andrew Waxman. “Avoiding Traffis Congestion Externalities? The Value of Urgency.” NBER Working Paper 26956.  


2.    Urban Mobility Report 

Annual data from 1982-2017 on various travel data including time cost of travel, delay metrics, travel times, and congestion costs. Report based on data from INRIX and FHWA and compiled by the Texas A&M Transportation Institute.


3.    Urban Congestion Reports  

Quarterly report on traffic conditions for 52 cities in the U.S. including congested hours, travel time index, and planning time index in levels and changes. Based on the National Performance Management Research Data Set and processed by the Texas A&M Transportation Institute. 

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