SUMMER DRIVING

In a separate study, IIHS determined that fatal crashes were most likely to occur in the summer and early autumn, on weekends, and in the late afternoon and evenings. Researchers looked at federal crash data from 1998 to 2014 to analyze these patterns.

July and August had the highest fatality rate, with both months having an average of 116 deaths per day during the study period. June and October each averaged 113 deaths per day, while September averaged 112. January and February had the lowest fatality rate at 92 and 93, respectively.

Traffic deaths were most likely to occur on Saturdays, with an average of 139 drivers or passengers killed on this day between 1998 and 2014. Sunday followed with a fatality rate of 122, while Friday was the deadliest weekday with an average of 118 deaths occurring daily on this day.

The Fourth of July was statistically the most dangerous time for drivers, with an average of 141 deaths each year. This was followed by New Year's Day, when an average of 135 traffic fatalities occurred.

A similar study conducted by IIHS in 2004 also determined that Independence Day had the most fatal crashes out of any day of the year. The average number of deaths in the more recent study was down 13 percent from 2004, while New Year's Day fatalities fell 5 percent.

The daily fatality rate also dropped, with an average of 106 traffic deaths per day between 1998 and 2014. This was down about 9 percent from the 1986 to 2002 period covered in the 2004 study, when daily traffic deaths averaged 117.

"Roadway deaths have declined since our original study, but the pattern of deaths is unchanged," said Farmer. "The riskiest times remain risky."