DETROIT -- U.S. Motorcycle deaths spiked 10 percent last year, topping 5,000 for the first time since 2008, according to a study done for a highway safety group.
The annual study for the Governors Highway Safety Association attributes the increase mainly to increased travel nationwide and better weather leading to a longer riding season in many states. Low fuel prices also contributed to a 3.5 percent rise in motor vehicle miles traveled last year over 2014, according to federal data.
But study researchers from Sam Schwartz Consulting say the biggest change that could cut motorcycle deaths would be restoring mandatory helmet laws in 32 states that don't have them for all riders.
The study used preliminary state data to count 5,010 motorcycle deaths last year, up 450 from 2014. The increase is consistent with preliminary numbers from the government that show traffic deaths overall rising an estimated 8 percent last year after trending downward for the past decade. That was the largest year-to-year percentage increase in a half-century.
The National Safety Council says about 38,300 people were killed on U.S. roads last year, and 4.4 million people were seriously injured. That would make 2015 the deadliest driving year since 2008.
"State and national data illustrate that motorcyclists are far more likely to be injured or killed in a crash than motor vehicle occupants," said Jonathan Adkins, executive director of the association, a nonprofit group representing state highway safety offices. The group will support evidence-based motorcycle safety measures, he said.
The association suggests that motorcyclists cut the risk of death by wearing government-approved helmets and bright clothing to be more visible. It also says to obey speed limits and never ride while impaired by alcohol or drugs.
There were 4,586 deaths in 2014, which the study authors said was abnormally low for recent years.
Motorcycle deaths increased in 31 states, fell in 16 and remained the same in three states and Washington, D.C., the study found.
The number of deaths last year is about double the annual number through the 1990s.