The number of people killed in U.S. highway accidents last year fell to 33,808, a drop of 9.7 percent from 2008, according to a report by the National Highway Traffic Safety Administration.

It was the lowest number of traffic deaths since 1950, even while estimated vehicle miles traveled rose 0.2 percent from 2008. Fatality and injury rates in 2009 were also the lowest ever recorded: 1.13 deaths per 100 million vehicle miles traveled, compared to 1.26 deaths in 2008. The total number of crashes declined by 5.3 percent from 2008.

Despite the small rise in vehicle miles traveled–usually a sign of a rebounding economy–NHTSA cited economic conditions as a possible factor in declining traffic deaths.

The Washington Post cited safer vehicle and street designs, increased seat belt use and aggressive enforcement of drunk driving laws as reasons for the decrease. Alcohol-related driving deaths fell by 7.4 percent, accounting for 10,839 deaths — nearly a third of total fatalities in 2009 — compared to 11,711 in 2008.