When you spend a good part of each day in traffic on the roadways of California, it may be tempting to treat the trip like a game, zipping around the slow cars and shaking a fist at the ones who cut you off. Some people take these attitudes too far, though, and put those around them in danger. The Insurance Information Institute reports that aggressive driving causes thousands of deaths on America’s highways each year. Which behaviors are responsible?

It may seem as if you have your vehicle under control, even if you happen to be going a bit over the posted limit. However, speeding killed more people in 2015 than DUI and distracted driving put together. In all, 8,778 drivers were involved in speed-related crashes that resulted in fatalities, and that made up 18.1 percent of the total fatal crashes that year. Behaviors in this category included racing and driving too fast for conditions, as well as driving over the posted limit.

Choosing to take a taxi after a party or staying at home to drink may keep you off the road when your blood alcohol content is too high, but medication, both over-the-counter and prescription, is also a factor in DUI deaths. Illegal drugs also contribute to the behaviors in this category, which makes up 11.1 percent of the fatal crashes. Distracted driving, which includes eating, grooming and looking at a map, as well as using your smartphone, figured at 6.7 percent of the total.

Failing to yield, stay in the proper lane or obey traffic signs and signals were all in the top ten dangerous driving behaviors, too. Sadly, many or most deaths from these crashes probably could have been prevented if the drivers had been more conscientious about following traffic laws.