Washington ? An economic downturn can have a bright side: U.S. highway deaths in 2008 fell to their lowest level since John F. Kennedy was president.

The recession and $4 per gallon gas meant people drove less to save more. Experts also cited record high seat belt use, tighter enforcement of drunken driving laws and the work of advocacy groups that encourage safer driving habits.

Preliminary figures being released by the government today show that 37,313 people died in motor vehicle traffic crashes last year. That’s 9.1 percent lower than the year before, when 41,059 died, and the fewest since 1961, when there were 36,285 deaths.

A different measure, also offering good news, was the fatality rate, the number of deaths per 100 million vehicle miles traveled. It was 1.28 in 2008, the lowest on record. A year earlier it was 1.36.

“The silver lining in a bad economy is that people drive less, and so the number of deaths go down,” said Adrian Lund, president of the Insurance Institute for Highway Safety. “Not only do they drive less but the kinds of driving they do tend to be less risky — there’s less discretionary driving.”

Fatalities fell by more than 14 percent in New England, and by 10 percent or more in many states along the Atlantic seaboard, parts of the Upper Midwest and the West Coast, according to the National Highway Traffic Safety Administration.

In the past, tough economic times have brought similar declines in roadway deaths. Fatalities fell more than 16 percent from 1973 to 1974 as the nation dealt with the oil crisis and inflation. Highway deaths dropped nearly 11 percent from 1981 to 1982 as President Ronald Reagan battled a recession.

The government said vehicle miles traveled in 2008 fell by about 3.6 percent, to 2.92 trillion miles, indicating many people adjusted their driving habits as gas prices fluctuated and the economy tumbled. The number of miles driven by motorists had risen steadily over the past three decades.