What’s the most dangerous time of day to walk across the road? A logical guess might be sometime in the middle of the night, when pedestrians blend into shadows on dimly lit streets, and drivers seem more likely to be tired or even drunk. But most fatal accidents actually happen just around twilight, as this chart shows.
Based on five years of data from the National Highway Traffic Safety Administration, the chart–created as a side project by user experience designer John Nelson–is nearly identical to one created by researchers in this 2010 study.
Why is twilight so dangerous? While the researchers had a few theories, one had to do with the way that our eyes adjust to light. “When you’re in a car, you’re in an enclosed box, and as it’s harder to tell as it’s getting slightly darker,” says Julia Griswold, a postdoctoral researcher at University of California-Berkeley who was one of the authors of the 2010 paper. “But pedestrians out on the street are less aware of their reduced visibility, so they might not be as careful as they should be.”
Later in the night, when it’s completely dark, pedestrians might be more likely to be cautious before stepping off the curb. Still, the chart shows that more people are hit and killed late at night than during the day. The researchers also found that accidents happen more often at certain times of year, and certain days of the week. In the winter, the evening commute is particularly bad. In the summertime, Friday and Saturday nights claim the most lives.
Every city is different, however, and there are more factors involved than just time of day–some places lack crosswalks or sidewalks, many need better lighting, and other factors like weather also vary. This chart looks at aggregate data for the whole country. But even in cities celebrated for walkability, pedestrians aren’t exactly safe. In New York City–ranked the most walkable city in the country in WalkScore’s 2014 survey–156 people were hit by cars as they were crossing streets or walking down sidewalks.
For cities trying to save pedestrian lives, the researchers say that focusing solutions on specific times might help. “It could be a matter of speed limit enforcement at that time of day–say in the winter at rush hour, since that’s a particularly heavy time,” says Griswold. Drivers (and pedestrians) could be taught why they need to be a little more careful at dusk. The researchers even suggest considering extending daylight savings time, so commuters would have better visibility when they’re driving home.
For now, just remember to look both ways when you’re crossing at dusk.