The Bloomberg administration has long trumpeted the safety benefits of its many roadway initiatives, hoping to rebuff critics who consider the policies to be undue interventions from a meddling city.

And in a report unveiled on Wednesday, the city’s Transportation Department says it has identified another benefit to pedestrian plazas, bike lanes and a rapid-transit bus system: Businesses that operate nearby have seen a pronounced bump.

“These projects are not just about the quality of life or aesthetics,” Janette Sadik-Khan, the city’s transportation commissioner, said in a phone interview. “In case after case, these projects really do set the table for economic development.”

The department culled data from the Department of Finance, drawing on sales figures reported by small businesses in areas that have been affected by the changes. (Larger chains report receipts centrally, rather than by location, so they could not be included, a spokesman for the department said.)

On Ninth Avenue, where the city has installed protected bike lanes, businesses from 23rd Street to 31st Street have seen a 49 percent increase in retail sales, compared with a boroughwide average of 3 percent over the same period, the report said.

On the north end of Union Square, where the city has installed a plaza and a protected bike path, the department said there was a 49 percent reduction in commercial vacancies. The borough has averaged an increase of 5 percent in commercial vacancies.

In Brooklyn, where a parking area on Pearl Street was converted into a plaza, retail sales have increased 172 percent for neighboring businesses, compared with 18 percent throughout the borough.

The department has even tied revamped bus service to economic improvement, citing a 71 percent increase in retail sales along Fordham Road in the Bronx. Ms. Sadik-Khan said increased ridership and faster-moving buses was most likely drawing more patrons to the businesses.

“Everybody’s got an opinion,” she said, “but we have the data.”