By Chris McCahill
Traffic deaths rose to 35,200 in 2015, a 7.7 percent increase from the previous year, according to preliminary estimates from the National Highway Traffic Safety Administration. This is the highest number of deaths since 2008, when there were 37,400.
Cyclist deaths increased by the largest amount (13 percent), followed by pedestrians (10 percent), and motorcyclists (9 percent), highlighting a critical need to focus on the safety of vulnerable road users.
The National Safety Council noted the significant number of traffic deaths midway through 2015, attributing it primarily to the increase in driving nationwide. The newly released numbers seem to validate a strong link between the two, depicted in Figure 1. While not a one-to-one relationship, the evidence suggests that the changes in driving might have a disproportionate influence on fatal crashes.
A recently published study from the University of Pennsylvania, which looks at the relationship between unemployment and traffic deaths, sheds some interesting light on this issue. After separating the effects of unemployment on risk (fatal crashes per VMT) and exposure (VMT per person), the author finds that risk makes up 88 percent of the relationship. This suggests that while changes in VMT may not fully explain traffic deaths, the influence of VMT is much greater when the economy is stronger. The author attributes this partly to higher rates of drunk driving and speeding (separate incidents), but also stresses that fatal crashes involving large trucks are much more common.
In addition, aggressive driving might also be on the rise, according to two surveys just released by AAA affiliates.
These factors mean that our roads could become considerably more dangerous as traffic increases, particularly for vulnerable users. As the CDC reported earlier this month, traffic safety in the U.S. continues to fall behind that of its peers, which have made considerable gains over the past 15 years.
Chris McCahill is a Senior Associate at SSTI.
By Chris McCahill