Although reasons for the recent rise have not been scientifically determined, experts suspect that smartphones and marijuana use are key factors in the deadly trend.
Bottom line: Texting while walking is especially risky in urban environments.
Combine that with drivers who are using their phones or touchscreens while driving, and it's a recipe for fatalities.
In addition, drugged driving and walking are believed to be a growing contributor.
The new Governors Highway Safety Association report released Wednesday estimates that 5,984 pedestrians were killed in the U.S. in 2017.
That would reflect essentially no change after a 9% increase in 2016 and a 9.5% increase in 2015, according to the National Highway Traffic Safety Administration.
The study indicates that the recent increases are not a statistical anomaly.
"It’s downright disturbing," said Richard Retting, director of safety for Sam Schwartz Consulting, who authored the report for GHSA. "People outside cars are dying at levels we haven't seen in 25 years."
The spike in pedestrian deaths comes despite improvements in vehicle safety, including the relatively recent introduction of automatic emergency braking systems, rearview cameras and collision alert technology.
But other potentially helpful developments are lagging. The Insurance Institute for Highway Safety has flagged poor headlights as especially problematic. Poor design and failure to adopt lights that swivel with the curvature of the road are hurting.
About 75% of pedestrian fatalities occur at night, making road illumination critical, Retting said.
But pedestrians are sometimes to blame, as well.
"We’ve got distracted drivers and we’ve got distracted pedestrians, and that is a deadly combination," said Rebecca Lindland, a Kelley Blue Book auto analyst. "At some point in time people both behind the wheel and walking in the street have to take responsibility for their behavior and put down the phone."
One option: new ordinances to outlaw smartphone use while strolling. The city of Montclair, Calif., recently banned walking across the street while using a phone or headphones. Honolulu has a similar law.
But widespread laws against distracted walking probably won't prevent people from accidentally wandering into the road.
"You can’t out-regulate distraction," Lindland said.
Increased use of marijuana is another potential factor causing the increase in deaths. In the seven states that legalized the drug for recreational purposes, as well as the District of Columbia, pedestrian deaths spiked 16.4% in the first half of 2017, according to the GHSA study. At the same time, deaths in other states fell 5.8%.
"We’re not making a definitive link here and saying this is an aha moment, but it’s a source of concern and we think greater attention needs to be paid to this issue," Retting said.
The GHSA estimates are based on an analysis of figures for the first half of 2017. NHTSA is expected to release the official numbers later this year.
Follow USA TODAY reporter Nathan Bomey on Twitter @NathanBomey.