NHTSA LogoAutomotive News reports U.S. traffic fatalities have increased by nine percent during the first six months of this year compared to the same period in 2011. A total of 16,290 people have died in road accidents between January and June, and while the figures have yet to be verified, they may represent the most deaths during the first six months of a year since 2009.

The data comes courtesy of the National Highway Traffic Safety Administration, which has not ventured a hypothesis on the factors behind the increase. Automotive News indicates other safety groups believe the jump could be attributable to culprits as wide ranging as the weather, the economy and fuel prices. A spike in the popularity of synthetic drugs and texting while driving could also be to blame.

It could be more than a year before NHTSA releases vetted figures, complete with the causes behind them.