Tens of thousands of vehicles continue to illegally pass school buses across the nation each day, according to the results of this year’s nationwide survey of stop-arm running.

More than 97,000 school bus drivers in 29 states participated in the 2014 edition of the annual survey, which is spearheaded by the National Association of State Directors of Pupil Transportation Services (NASDPTS).

A total of 75,966 stop-arm violations were counted in one day. NASDPTS officials said that this sample points to more than 13 million violations in a 180-day school year.

“We know that students are far safer in school buses, but when they are outside the bus, they are more vulnerable to injury or death,” NASDPTS President Max Christensen said. “There are nearly a half million school buses on the road each day in the United States. This survey captured only a fraction of the violations that bus drivers and traffic officers know all too well are occurring each and every day.”

Here are some key details on the 2014 survey results:

• Of the total 75,966 stop-arm violations counted, 98% were on the left side of the bus (the driver’s side), and the other 2% were on the right side.

• More vehicles passed buses from the front (58%) than the rear (42%).

• 45% of the violations occurred in the morning, 5% were mid-day and 50% were in the afternoon.

This is the fourth year that NASDPTS has conducted the national survey. The annual totals have ranged from a high of 88,025 in 2012 to a low of 75,966 violations this year. The number of school bus drivers participating has varied each year, which may explain the fluctuations in the violation totals.

Many states have taken steps to cut down on illegal passing of school buses, including increasing the penalties for violations, launching public awareness and law enforcement campaigns, and allowing the use of exterior cameras on school buses to capture violations.

In June, South Carolina enacted a law allowing the use of stop-arm cameras.

In March, Wyoming passed a bill that requires all school buses to have stop-arm cameras as of the 2016-17 school year. Up to $5 million will be appropriated to reimburse school districts for 100% of the costs of the video surveillance systems.

The Wyoming bill was spurred by a 2011 incident in which an 11-year-old girl was struck and killed by a vehicle passing her school bus as she was crossing the street.

In the 2012-13 school year, six children in the U.S. were fatally struck by vehicles passing their school bus, according to national data compiled by the Kansas State Department of Education.

“Any driver who passes a stopped school bus illegally is endangering children and his or her future,” Christensen said. “These results highlight the potentially tragic consequences of saving a few seconds by passing a school bus. It can be devastating not only for the victims and their families, but also for the motorist who hits a child and will have to live with the sad consequences.”

Detailed results from the NASDPTS survey for 2014 and previous years can be found at www.nasdpts.org/stoparm.