North Dakota took the title of best performing highway systems in America for the ninth year in a row, while Alaska had the worst-performing, least cost-effective highway system in the nation

, according to an annual Reason Foundation study that measures each state's road conditions and expenditures.

Across the country, over half of all state-owned highways are congested, and 25 percent of bridges are deficient or functionally obsolete. Rhode Island and Massachusetts have the worst bridges, with over half needing repair and improvement.

"This year's report shows the difficulties that many states are having when it comes to making across-the-board progress in road conditions," said David Hartgen, lead author of the highway report and senior fellow at Reason Foundation. "In many cases, we see two steps forward, one step back. We saw improvement in five key categories in 2007, but also found that over a quarter of the nation's bridges are rated deficient. Urban interstate conditions are worsening again. And real progress in reducing urban congestion has slowed to a crawl."

While the total amount of spending on state highways grew 10 percent to over $109 billion in 2007, a greater amount of that spending never made it to roads. In 2007, administrative costs rose nearly 13 percent, accounting for 7.2 percent, or nearly $8 billion, of state highway spending, according to the study.

Delaware experienced the largest jump in rankings, moving from 28th to 11th by cutting spending without sacrificing road condition. Michigan moved up to 30th from 42nd, thanks to an improvement in rural pavement condition.

Four states fell in the overall rankings by double-digits including Missouri, Oregon, Vermont and Indiana, which fell 16 spots because of a sharp decline in urban interstate condition and an increase in spending per mile.

The Reason Foundation's 18th Annual Highway Report examines state highway systems in 11 categories, including congestion, pavement condition, fatalities, deficient bridges and total spending. The annual report is based on information that each state reported for the year 2007.

To access the full report, click here.