Traffic research firm Inrix compiled data for Governing measuring traffic congestion in 100 metro areas. The company collects data via mobile application, GPS systems in personal and commercial vehicles and road sensors. Figures listed reflect average delays for all types of roadways: arterial roads, highways and city streets for entire metropolitan regions.
Traffic congestion data was measured from May 2011 to May 2012.
Zoom in and click a city on the map to display traffic delay data for its metro area. Larger makers represent a higher Inrix commute delay index, which refers to the percentage of average additional time added to a Friday afternoon commute between 4 and 7 p.m. An index of 20, for example, would mean a trip taking 30 minutes without traffic is delayed six minutes.
