The number of pedestrians killed in traffic in the United States is approaching a three-decade high, contributing to what has been an “alarming rise” in such deaths in recent years, according to a new study.

An estimated 6,227 pedestrians were killed in traffic in 2018, according to the study from the Governors Highway Safety Association, a projection based on data from the first half of the year. That figure represents a striking rise from a decade earlier, when 4,109 pedestrians were killed in traffic.

“I’ve been in this business for 36 years and I’ve never seen a pattern like this,” said Richard Retting, who wrote the report and has worked in a variety of traffic engineering and safety roles for the New York City Department of Transportation, the Insurance Institute for Highway Safety and other federal and local transportation agencies.

The report cited alcohol use, speeding, unsafe infrastructure and the prevalence of SUVs as some of the biggest problems contributing to the fatalities. It also suggested that the increased use of smartphones may contribute to such deaths.