Congestion on the nation's highways is getting worse, and the worst place to be is in California.

The Texas Transportation Institute issued its list of the top 10 most congested cities in the U.S. Los Angeles took the top spot, followed by San Francisco-Oakland, Seattle, Washington D.C., San Diego, Chicago, Boston, Portland, Atlanta and Las Vegas.
In addition, TTI found that the average person spends 36 hours a year sitting in traffic, compared to 34 hours two years ago, and 11 hours in 1982.
California is home to three of the top 10 congested cities. In Los Angeles, residents in 1999 averaged 56 hours a year in bumper-to-bumper traffic. Half of California's urban freeways are considered congested because they carry more traffic than they were designed to handle.
Based on the TTI results, The Road Information Project released a report, "Stuck in Traffic," about the link between highways and the economy. TRIP says growing levels of traffic congestion could hamper the nation's economic prosperity and result in higher costs to consumers because of increased shipping costs as well as higher costs to motorists stuck in traffic.
According to TRIP, 72% of the estimated $7 trillion worth of goods shipped nationwide is transported on trucks. An additional 12 percent is transported by courier services, bringing the total to 84% of all goods s hipped that travel on the nation's roads and highways. Freight shipments are expected to double in most parts of the country over the next 20 years, according to the group, with trucks projected to carry 82% of the new total amount of tonnage.