Motorcycle fatality rates in the U.S. increased for the third consecutive year in 2012, according to data compiled by the National Highway Traffic Safety Administration.

The 2012 Fatality Analysis Reporting System (FARS) data from NHTSA counted 4,957 motorcyclists and passengers killed in traffic crashes last year, compared to 4,630 the year before. Total injury rates for motorcyclists also rose, seeing a significantly large 15% increase to 93,000 people from 81,000 in 2011.

Motorcyclists accounted for 14.8% of all traffic fatalities but only 3.9% of all traffic-related injuries. According to the FARS data, there were 33,561 traffic fatalities in the U.S. in 2012, including motorcycles, cars, trucks, pedestrians and bicyclists, a 3.3% increase over 2011. Meanwhile, overall traffic injuries in 2012 increased by only 6.5% to 2,362,000.

A continuing worry is the dangers of driving or riding while drunk. In 2012, there were 10,322 fatalities where one party (not necessarily the person killed) had a blood alcohol content level of 0.08 g/dL or greater, representing 30.8% of all fatalities. Alcohol was a factor in the deaths of 1,390 motorcyclists.

Another worry more specific to motorcyclists, and one recently raised by a government task force and the American Motorcyclist Association, is helmet use. According to the NHTSA report, states without universal helmet laws accounted for 1,858 fatalities from riders without helmets. Meanwhile, in states with universal helmet laws, unhelmeted fatalities totaled just 178 (NHTSA said these states were nearly equivalent in terms of combined population size, eliminating that as a factor in the large difference.)

Click here to read the full 2012 Fatality Analysis Reporting System report. For a state-by-state look at traffic fatality statistics, visit the NHTSA site.