In Chicago, the average total time wasted in traffic dropped to 41 hours in 2007. That's down two hours from the year before.
L.A.'s traffic is still the nation's worst at 70 hours wasted each year. Still, even that is an improvement.
In individual cities, Los Angeles traffic is getting better but is still the worst in the nation. Washington's is getting worse, now ranking second.
The average U.S. driver languished in rush-hour traffic for 36.1 hours in 2007, down from 36.6 hours in 2006 and a peak of 37.4 hours in 2005, according to a study being released Wednesday by the Texas Transportation Institute. Total wasted fuel also edged lower for the first time, from 2.85 billion gallons in 2006 to 2.81 billion, or roughly three weeks' worth of gas per traveler.
The records go back a quarter-century, to 1982.
The last time traffic congestion had declined was in 1991 amid a spike in oil prices during the first Gulf War.
This time, demographers attributed the decrease to a historic cutback in driving as commuters reduced solo trips, took public transit or carpooled after gas prices surged toward $4 a gallon and then the economy faltered. The housing downturn beginning in 2006 also has played a factor by reducing U.S. migration to far-flung residential exurbs.
But it won't last, assuming the economy recovers.
"Congestion won't be as bad as before for a while, but it will still be very frustrating, very unreliable and it will take a lot of time out of your day," said Tim Lomax, researcher at the Texas Transportation Institute, which is part of Texas A&M University. "The average traveler still needs 25 percent more time for their rush-hour trips."
The Los Angeles metropolitan area, with its car pool lanes and emerging mass transit, shed two hours of wait-time in rush-hour traffic. Still, its sprawling freeway system remained the nation's worst for congestion, with drivers wasting an average of 70 hours in 2007.
Other large metro areas showing congestion declines were San Francisco, Atlanta, Chicago, Dallas-Fort Worth and Seattle.
In contrast, the Washington, D.C., area had more bumper-to-bumper traffic, surpassing Atlanta as the second worst in congestion. With the Washington regional economy faring relatively well, drivers heading to work in the nation's capital and surrounding suburbs wasted 62 hours in rush-hour traffic in 2007, up from 59 hours.
Houston, Las Vegas, Charlotte and Raleigh-Durham, N.C., had worse or equally bad traffic compared with the previous year, victims of a fast-growing population that outpaced roadway capacity.
In Montclair, Va., the 30-mile commute to Washington, D.C., has always been so bad that Ray McInerney, 29, and three co-workers decided years ago to car pool. He has no major complaints about the ride to their jobs at the Interior Department -- so long as they leave by 6 a.m. and head home at 4 p.m., taking advantage of high-occupancy vehicle lanes along I-95.
Shuttling around the region for his 12-year-old son's baseball practice and tournaments is a different story, but McInerney says he endures the traffic along with everyone else because cutting back on trips is not an option.
"It's definitely something that came to mind when gas prices came close to four dollars," he said. "But we would have to have serious cutbacks for him not to be able to play."
The Texas Transportation Institute analyzed state and Federal Highway Administration data for 439 urban areas. It estimated:
--The overall cost of U.S. traffic congestion in 2007 reached $87.2 billion, more than $750 for every traveler.
--The amount of wasted time in traffic totaled 4.2 billion hours, nearly an entire work week for every traveler.
--After Los Angeles and Washington, the most congested metro areas were Atlanta, Houston, San Francisco, Dallas-Forth Worth, San Jose, Calif., and Orlando, Fla.
--The least congested metros were Lancaster-Palmdale, Calif., and Wichita, Kan., where drivers were delayed an average of six hours a year.
The report urged state and federal governments to act now to develop highways or mass transit, since these programs can take 10 to 15 years to complete. It said short-term fixes such as rapidly removing crashed vehicles and timing traffic signals also would help, while employers can offer flexible work hours and telecommuting to reduce travel during traditional rush hours.
The findings come as the Obama administration has signaled that it wants to keep transportation funding at current levels for 18 months, rather than move forward on a proposed six-year, $500 billion bill that would increase highway aid 40 percent and double transit funding. There are questions about how to pay for that.
Robert E. Lang, co-director of the Metropolitan Institute at Virginia Tech, said while the recession is altering how many people work, live and travel, that won't be enough to hold back traffic congestion. With the U.S. growing by three million people each year, the nation's aging infrastructure won't be able to keep up without broad upgrades -- especially once the economy picks up again.
"It's the lull before the coming storm," he said.
The Associated Press contributed to this report.