It’s become a truism that Americans are driving less due to high fuel prices. Here are five signs that signal a decline in demand:

1. Drop in volume: The fall in U.S. oil demand in the first half of 2008 was the biggest in 26 years, according to the EIA.

2. Less time on the road: Americans are spending less time behind the wheel, according to the Dept. of Transportation

3. Taking the train : A record number of riders are turning to mass transit to get around

4. Fewer buying gas : Retail gas sales have dropped below year-ago levels

5. Safer roads : Fewer drivers mean fewer road accidents, according to Warren Buffett. Berkshire Hathaway is the parent company of Geico, one of the largest U.S. auto insurers.

Is the writing on the wall? Share your signs of dropping oil demand.

For full coverage of the oil market, click here.

More Americans are leaving their cars at home and jumping on buses, trains and trolleys as retail gasoline prices approach $4 per gallon, the American Public Transportation Association said in a report.

“There’s no doubt that the high gas prices are motivating people to change their travel behavior,” APTA president William W. Millar said. (For the full story, click here.)

Record high gas prices are forcing many drivers to spend less time behind the wheel. Data from the Department of Transportation on May 23 shows Americans drove 11 billion miles less in March than a year earlier — the sharpest year-on-year drop in the history of the agency’s reporting.

The government agency also reported that highway miles driven in March fell 4.3 percent from a year earlier — the first March decline since the last major oil shock in 1979.

Have you started taking mass transit more often in light of high gas prices?

Related blog: Who wants a 4-day work week?

For full coverage on the rising cost of oil, click here.

(Editor’s note: This blog was originally posted on May 23 and updated on June 2, 2008)