Several of the city's homeless take shelter at the McPherson Square Metro station on Jan. 25 in Washington. Volunteers Brian Gober, of the DowntownDC Business Improvement District, left, Girum A. Gebretsadik, of Pathways to Housing DC, middle, and Jordan Gulley, also of Pathways to Housing DC, conduct an annual census of homeless people in the District. (Amanda Voisard/For the Washington Post)

The number of homeless people in the nation’s capital has declined 11 percent since last year, a drop that was driven by reductions in the number of homeless families counted in the District and mirrored declines in homelessness throughout the region, according to a report released Wednesday.

The reduction was a welcome development for Mayor Muriel E. Bowser in her struggles to curtail the District’s high rate of homelessness.

But the news was not all good. The city’s homeless population of 7,473 remains higher than it was in 2015 — Bowser’s first year in office — and has increased 8.9 percent over the last five years.

“These results show that our efforts to prevent homelessness and connect more residents to safe and affordable shelter are paying off,” Bowser said in a statement. “We still have more to do, but we have made significant progress over the past two years, and we will continue this work until every D.C. resident has a safe place to call home.”

The District accounted for about two-thirds of the homeless people counted in the regional survey, which was published by the Metropolitan Washington Council of Governments. The count is based on reporting by homeless shelters and a one-time count by volunteers who walked the streets on the night of Jan. 25.

Most jurisdictions saw declines in homelessness from 2016, though the population was flat in Prince William County and increased by 33 percent in Arlington County.

Kathleen Sibert, the president and chief executive of the Arlington Street People’s Assistance Network, noted that because Arlington has a relatively small homeless population, modest fluctuations can create dramatic-looking percentage increases or decreases.

Fifty-eight more people were counted in 2017 than in 2016, bringing the total homeless population in Arlington County to 232, nearly the same number of people as were counted in 2015.

“We look at the trend line over several years more than the year-to-year anomalies,” Sibert said. Since 2013, the county’s homeless population has dropped 52 percent, she noted.

The county has also been aggressively seeking to eliminate homelessness for several years by using a “housing first” approach that seeks to break down barriers among the agencies and departments that provide services to people who don’t have shelter.

“We feel positive about the direction Arlington is going, but tomorrow someone new is becoming homeless,” Sibert said. “We’ve made strides, but we have a way to go.”

In the District, long-term trends in the homeless count tell two stories. There were 3,578 homeless adults without children in 2017, a decrease from the 3,690 five years ago. Over the same five-year period, however, the number of homeless people in families — adults and children — grew to 3,890 from 3,169.

Nevertheless, there were signs in the newly released count that the city is making headway against the problem of family homelessness: The number of homeless people in families decreased by 16.6 percent from 2016.

“The numbers are turning in the right direction,” said Kristy Greenwalt, director of the D.C. Interagency Council on Homelessness. “It’s good evidence that the reforms we are making are working.”

Greenwalt said those reforms — outlined in a plan Bowser released during her first year in office — include efforts to prevent people from becoming homeless in the first place and to move them back into housing as quickly as possible when they do.

Kate Coventry, a senior policy analyst at the D.C. Fiscal Policy Institute, said the count suggests that city policies to lower homelessness are beginning to have an effect.

But she said the problem that is driving many families into homelessness in the first place — a lack of affordable housing — is still far from being remedied.

“That’s not a problem that’s going to be fixed in a year,” Coventry said.

Patricia Sullivan contributed to this report.