Figures from the 2000 census show about 76 percent of workers 16 and older drive alone to their jobs, up from 64 percent two decades earlier and 73 percent in 1990, even though commutes are taking longer.
For many, a long commute is a necessity, the price for larger and more affordable homes in the suburbs. And it's the result of congested highways choked by the urban sprawl that has turned many suburbs and even rural areas into burgeoning communities and business centers.
Stacy Brown said traffic has gotten worse in the four years since she started driving 25 miles from Frederick, Md., to her job as a receptionist in Rockville, Md., just north of Washington. Still, she prefers driving.
"I'd rather sit in my car alone in air conditioning in traffic than wait for a train on a hot platform," Brown said before pulling away from a gas station where she fueled up for the morning commute.
Alan Pisarski, a former deputy director of planning for the Department of Transportation who researches commuting trends, said as more people own homes, they face longer drives to work.
"There's a trade off with the mortgage and commuting time," he said.
The Census Bureau asked people their "usual" mode of transportation to work. So, for example, someone who drives to a train stop would have to choose one or the other as the primary way to work.
Carpooling was the second-most-popular way to work, with 12 percent of Americans saying they ride with friends. That was down from 20 percent in 1980 and 13 percent in 1990.
Public transportation was used by 5 percent of Americans, about the same as in 1990, while those who walk to work fell from 4 percent to 3 percent. People who work from home went up slightly to 3.3 percent from 3 percent.
Solo driving rates rose in every state in 2000 except Washington and Oregon, which saw small increases in public transit and work-from-home options. And the average one-way commute rose to 25½ minutes, about three minutes longer than 1990.
The increase in solo drivers came despite continued government efforts to encourage public transportation, major fluctuations in gas prices and warnings about the harmful effect of car exhaust on the environment.
Michael Marsden, an Eastern Kentucky University professor who teaches a course in the automobile's role in society, said America's love affair with the car means solo drivers always will constitute a large portion of commuters.
"People want to drive their own cars, decide when they want to go, where they want to go," he said. "In some ways, the only time people are in charge are when they are in their cars, not at home or at work. It's a very psychologically satisfying thing."
Small metropolitan areas in the Midwest and South had the highest rates of solo drivers, led by the 87 percent of Ohio residents who commute in the Huntington, W.Va.-Ashland, Ky. metro area. For metro areas that encompass more than one state, the Census Bureau calculated rates for drivers in each state.
Saginaw, Mich., and two Ohio cities — Youngstown and Canton — had solo driving rates around 86 percent, the 2000 census found. Pisarski said limited public transit options in those areas force more people to drive alone.
Washington, D.C., had the lowest rate, 38 percent, followed by New York City at 44 percent. Both cities have a high percentage of workers who use mass transit.
For many cities, the shift to the suburbs means the need for massive highway construction projects to accommodate more solo drivers.
Work on such a project is under way in the Denver metropolitan area, home to Douglas County, the fastest-growing county in the nation. The Transportation Expansion Project, dubbed "T-Rex," will add more lanes to Interstate 25, the major north-south route into Denver. A light rail line also will be built along the corridor.
Denver native Scott Yates said the project is sorely needed. He grew so frustrated with traffic he started an Internet-based business giving subscribers e-mail updates of traffic.
"It was horrible before, it's now horrible squared because of the construction," said Yates, who works out of his home. "But at least people know five years from now it won't be gridlock all the time."