INRIX, based in Kirkland, Wash., said in a news release the declines reflect a soft economy and high gas prices, leading Americans to drive less.
Traffic congestion declined the most in cities where gas prices were higher than the national average in April 2011, including Los Angeles, San Francisco and Honolulu.
Cities where employment growth exceeded the national average, including Tampa, Fla., Houston and Austin, Texas, had some of the biggest increases in traffic congestion. Cities with moderate employment gains and fuel prices below the national average, including Atlanta and Miami, also showed big increases in traffic.
Cities with the worst traffic include Honolulu, where drivers spent an average of 58 hours in traffic last year; Los Angeles, where drivers spent an average of 56 hours in traffic; and San Francisco, where drivers spent an average of 48 hours in traffic. Other cities among those with the worst traffic include New York, Bridgeport, Conn., Washington, Seattle, Boston and Chicago.
The report also tracked the worst traffic corridors of at least 3 miles in length that have heavy traffic daily. Eight of the worst 10 corridors were in Los Angeles or New York. The others were in Pittsburgh and San Francisco.
Wisconsin business offering 'therapeutic cuddling' forced to close
Megyn Kelly: Santa Claus and Jesus are both white men