Several hours after sunset last week, Akil Nesby was walking on Central Avenue in Capitol Heights, in Prince George’s County. Although the street has sidewalks, he was walking in one of the nine lanes of traffic when an eastbound SUV struck and killed him.

Prince George’s averages about 22 pedestrian fatalities a year, and Maryland had more than 1,000 such incidents between 2008 and 2017. Nationally, 49,340 pedestrians were killed in the same period.

Police are still investigating what happened to Nesby, 39, who lived in Northeast Washington. Was he crossing the street? Had he wandered into traffic? What was his state of mind? Unquestionably, he had stepped into a maelstrom of traffic about 8:30 p.m., nine lanes of it on Central Avenue crossed by another seven lanes at the intersection with Hampton Park Boulevard.

“One of the most alarming things is how this problem is getting worse even though traffic fatalities overall are going down,” said Emiko Atherton, the author of a study on pedestrian deaths that will be released Wednesday by the group Smart Growth America. “Pedestrian safety is not getting better. We’re on record highs in killing pedestrians. We haven’t hit this height since 1990.”

Atherton used the national pedestrian fatality count from 2008 to 2017 to create what she called the “pedestrian danger index,” using data compiled by the National Highway Traffic Safety Administration.

Other than Delaware, which ranked third on the list of most dangerous states, the data was heavily tilted toward states in the South and Southwest, with Florida leading the list for a rating more than three times higher than the national average.

“If this were a plane [crash] we were talking about, or this was a communicable disease, it would be on the news every night. But instead it barely gets any attention,” Atherton said.

By Atherton’s danger index, Maryland (18th) and Virginia (23rd) straddle the national average. The District ranked 36th, but AAA has calculated that more than 40 percent of all traffic fatalities in the city last year were pedestrians.

“The largest number of crashes involving pedestrians in the [D.C.] region in 2017 occurred during the months of November, October, December and January, in that order,” said John B. Townsend II, spokesman for AAA Mid-Atlantic.

Atherton says there’s no mystery in finding the path to minimize pedestrian deaths.

“It’s building sidewalks, but it’s also building smaller blocks on a more human scale, so lots of people have more opportunity to cross,” she said. “It’s having good crosswalks, but also the ample time for people to cross them. It’s having more traffic calmings so that cars are slowing down, because speed is so correlated with your likelihood to die if you’re a pedestrian.”

She says suburban and city streets should be designed to do more than speed cars to their destination. The result, she said, is that ‘“highway” designs are imposed on neighborhoods, and those designs put pedestrians and bicyclists in jeopardy.

“We’re talking about not just how to how to set better speed limits, but how we design our roadways to better reflect the speeds we want,” Atherton said. “The thought is that if we just set better speed limits, people will slow down, but the fact of the matter is that that’s not really true.”

Her report says: “Federal dollars and policy helped create these unsafe streets in the first place. And federal funds, policies, and guidance have a significant role to play in fixing these streets.”

As Congress begins to plan for a new highway and transit bill this year, Atherton wants Capitol Hill to apply pressure on states and municipalities that engineer roads, including denying federal funding for poorly planned highways.

“What if every time someone was struck and killed, they had to look at the design speed of the road?” she said.

Atherton said that designers invoke the 85th-percentile rule when they set highway speed limits.

“We set it to where 85 percent of most drivers are going to drive, and we only assume 15 [percent] are going to speed,” she said. “The problem with that is that states and some cities continue to build roads that are designed for much higher speeds.”

Her report made particular note of the high rate of pedestrian deaths among people of color and in low-income communities.

“There are neighborhoods that have far less [federal, state or local] investment in transportation, specifically pedestrian infrastructure in poorer communities of color,” Atherton said.

She said the elderly, in Florida in particular, are not more prone to fatal pedestrian accidents than anyone else but acknowledged the problems faced by older people.

“Even if you have infrastructure, as you age you develop different mobility challenges and it’s harder to get around,” she said.

Atherton pointed out that a number of improvements have made cars safer — air bags, seat belts, automatic braking systems — but overall she sees vehicles that have grown more menacing as they’ve gotten larger.

“We’re seeing more SUVs. We’re seeing more trucks on the road, and those have been shown, when they strike a pedestrian, they have much more likelihood of killing someone,” she said.