According to the Federal Highway Administration, Americans drove fewer miles for the sixth straight month in August, logging 1.7 percent fewer miles amid high gas prices and a struggling economy.

In total, Americans drove 263 billion miles in July. That's 4.6 billion fewer miles than the same month last year, the Federal Highway Administration said.

Through the first eight months of the year, Americans have driven 1.978 trillion miles, the lowest tally since 2003.

In total, Americans have driven twenty-six billion fewer miles this year, down 1.3 percent. That's equal to more than one million trips not taken around the world.

At the same time, Americans have also been buying less gasoline. For the week ending Oct. 14, MasterCard SpendingPulse's survey found retail gasoline purchases declined 3.1 percent. Gas prices are still up about twenty percent over a year ago in the Midwest.

Travel in Michigan is off even more than the national average. In August compared to a year ago, travel fell 2.5 percent in Michigan to 8.46 billion miles. Travel was down 3.2 percent in July to 8.5 billion miles, according to preliminary state figures.

The federal report is based on continuous hourly traffic count data at 4,000 traffic counting locations nationwide. It can be seen at www.fhwa.dot.gov/ohim/tvtw/11augtvt/11augtvt.pdf