TTI prepares the definitive national study documenting congestion costs and trends, the annual Urban Mobility Report. The 2010 Urban Mobility Report paints the most accurate picture yet of traffic congestion in the 439 U.S. urban areas. Thanks to the wealth of speed data provided by INRIX, a leading private-sector provider of travel time information, the current report offers a greatly enhanced picture of congestion on a city-by-city basis.The report was prepared by TTI researchers David Schrank and Tim Lomax.