WASHINGTON (Bloomberg) -- The number of people killed on U.S. highways fell in 2011 for the sixth straight year, the longest streak of declines in the nation's history.
Crash fatalities dropped 1.7 percent to an estimated 32,310 from a year earlier, the National Highway Traffic Safety Administration said Monday in a report.
The fatality rate, or the number of people killed for every 100 million vehicle miles traveled, slid to 1.09 from 1.11 in 2010.
The report, which is preliminary until final figures are released later this year, gave no reason for the decline.
The drop coincided with U.S. drivers traveling 1.2 percent fewer vehicle miles as gasoline prices rose 6.7 percent, according to motoring group AAA.
The U.S. government has tracked deaths on U.S. roads since 1899, when 26 people died in motor vehicle crashes.
Fatalities declined in all four quarters last year after rising in 2010's third and fourth quarters. Those increases followed 17 consecutive quarters of decreases.