During Which Month Is It Riskiest to Drive in the United States?

OBJECTIVES: This study examined the variation in the U.S. road fatality rate per distance driven across the months of the year. METHOD: The monthly fatality rates were analyzed for a 13-year period from 1994 through 2006. RESULTS: The results indicate a systematic seasonal variation in the road fatality rate, with the highest rate in October and the lowest rate in March. CONCLUSION: The obtained seasonal variation in the road fatality rate is likely a result of a joint influence of several factors that exhibit seasonal variations themselves (the duration of darkness, consumption of alcohol, proportion of older drivers, amount of leisure driving, and inclement weather).