After a nearly decade-long decline, deaths on U.S. roadways started rising again two years ago as gas prices dropped and more Americans got back in their cars. Now, a new study has found that cyclist deaths increased at a higher rate than those of drivers, walkers, or any other road user. Researchers also saw an uptick in the age of the victims.

In 2015, the most recent year with available data, bicyclist deaths rose by 12.2 percent to 818, up from 726 in 2014. According to the report issued by the Governors Highway Safety Association (GHSA) and funded by State Farm, that's the highest number of cycling deaths since 1995.

An average of 55 additional cyclists have died each year since 2011. While that seems like a lot—and cyclists are indeed seeing their death rates rise faster than those of other groups—it still constitutes only a small portion of the more than 35,000 total traffic deaths in the U.S. in 2015. (Overall roadway fatalities rose by 7.2 percent.)

RELATED: The Kalamazoo Car-Bike Crash Survivors, One Year Later

In decades prior, children and teens made up the bulk of cycling deaths, but that has changed dramatically, according to the report. The average age of a cyclist who died riding in 2015 was 45, and the vast majority—85 percent—were men. In 1975, there were 786 deaths of cyclists under age 20, compared to 212 over 20. In 2015, there were only 91 deaths for those under 20 and 720 deaths for those over 20.

Researchers found that most of the fatalities involved incidents where the driver of the car did not see the cyclist, while the cyclist expected the driver to yield and instead was unable to avoid a collision.

Dulcie Canton recalls what it was like to be hit by a car while on a bike:

preview for Left for Dead - And the Police Did Nothing

Is there cause for alarm? While 818 cycling deaths are 818 too many, the report notes that larger and more diverse numbers of people are biking in general, which at least partially accounts for the uptick. According to the Alliance for Biking and Walking, the percentage of adults biking to work in the U.S. rose from 0.4 percent in 2005 to 0.6 percent in 2013, with much of the growth happening in large cities. The GSHA found that 34 percent of Americans over age three rode a bike sometime in the last year.

While cycling deaths have increased, then, so has the number of overall cyclists. It's hard to gauge whether the former is proportional to the latter, but to the GHSA one thing is clear: With bicycling growing in popularity and more cyclists hitting the streets daily, more should be done in terms of laws, infrastructure, and behavior to protect them.

“State highway safety agencies are tasked with addressing road user behavior through public awareness, so they are uniquely positioned to educate people about the safety benefits of engineering improvements and build support for better roadway design,” said GHSA executive director Jonathan Adkins in a release. “While engineering solutions are vital, states and communities cannot solely build their way out of the problem. These changes should be accompanied by education and enforcement to be most effective.”

RELATED: Dealing With Fear After a Crash

After all, the study found no clear correlation between location or time of day and the likelihood of a fatal crash. Cycling deaths occurred at about the same rate during the day and night, while 73 percent took place away from an intersection. Other data showed that 37 percent of the crashes involved alcohol consumption by either the cyclist or the driver.

The report made 30 recommendations for increasing bike safety, including more training for law enforcement to understand state and local laws designed to protect cyclists, partnering with bicycling and community organizations to amplify driver and cyclist safety messaging, and pairing infrastructure improvements with public education.

“We need to ensure that bicyclists and motorists can share roads safely,” said Chris Mullen, director of technology research at State Farm, in a release. “Unfortunately, bicyclists are vulnerable and much more susceptible to serious injury or death when on the roads with vehicles. That’s why it is so critical that we examine the factors surrounding these crashes and leverage a variety of proven tools to improve bicyclist safety nationwide.”

Keep up with the latest cycling news by subscribing to our newsletter.