July 4th arrives amid shift in driving habits

— -- The nation heads into the Independence Day holiday weekend amid the longest and steepest decline in driving since the invention of the automobile.

Since the number of miles traveled by motor vehicles in the USA peaked in November 2007, the nation's 12-month total has dropped by 123 billion miles, or slightly more than 4%. That's a bigger decline than the drop of just above 3% during the 1979-80 Iranian revolution that triggered a spike in gasoline prices in the USA.

The 4% drop is the equivalent of taking between 8 million and 10 million drivers off the road.

"We may be witnessing the beginning of a fundamental shift in American driving habits," says Ed McMahon, senior research fellow at the Urban Land Institute, a non-profit group that promotes innovative development.

The Federal Highway Administration's miles-traveled report for April, the most recent available, suggests a slight flattening out. While April's total was up 0.6% from April 2008, continuing rises in joblessness and gas prices are likely to limit driving, McMahon says.

As the USA prepares to celebrate the Fourth of July, many Americans are choosing to watch fireworks close to home. AAA projects that the number of people taking a trip of 50 miles or more this holiday weekend will drop 1.9% from a year ago. The leisure travel organization attributes the projected decline to uncertainty about the economy, "especially rising joblessness and sagging personal incomes." The recent spike in gas prices also might be a concern, AAA says.

Gas prices were the driving force behind the nation's change in driving habits, says analyst Alan Pisarski, author of Commuting in America. "When people saw $3 a gallon, when they saw $4 a gallon, it was something akin to sticker shock. It really did have an effect on people's behavior." He says people started taking transit, carpooling, merging trips and cutting back on vacation travel. Many stayed with alternative modes of transportation even after gas prices retreated last year.