A new city study released last week takes stock of business activity and consumer spending along Dorchester Avenue, as several city agencies and a panel of neighborhood residents continue the planning stages of the Dorchester Avenue Project, which will reshape the thoroughfare's streetscape and develop an economic master plan between now and 2010.

The Business Analysis Report, unveiled by Mayor Thomas Menino at the monthly Dorchester Board of Trade luncheon last week, uses census data and the work of a private data management firm to analyze economic trends in the "Dorchester Avenue Corridor," defined as the 42 census blocks that abut Dorchester Avenue. By that count, the Avenue Corridor comprises 40 percent of Dorchester's total area and 13 percent of Boston's 48.4 square miles. As of the 2000 census, the corridor also contained 49,542 people, more than half of the neighborhood's total population.

The study states that based on market research collected by Claritas Data, the corridor population had decreased by 2005 to 47,686 residents, a 3.7 percent drop.

But the earning power of residents near the Avenue appears to be increasing, though those figures remain lower than citywide averages. According to the 2000 census, the per capita income in the corridor was $17,849; a thousand dollars higher than the neighborhood average, but well below the citywide average of $23,353. Median household income matched city averages more closely, to within $1,000.

By 2005, there were signs of significant improvement: a 14.3 percent increase in median household income, and a 17 percent decrease in the number of families earning less than $25,000. And at the other end of the spectrum, the number of households earning more than $100,000 increased by 65.7 percent.

Regarding business along the avenue, the study found that almost half of the 99 commercial properties sold between 1995 and 2005 were in the St. Marks and Fields Corner neighborhoods, and that fully a third of the 1,474 recognized Dorchester businesses were located in the Avenue Corridor.

That estimate of the neighborhood's business population is significantly lower than a recent study released by UMass-Boston that found 3,000 businesses in Dorchester. That report, which combined GIS (Graphic Information Systems) mapping technology at UMass-Boston with input from the city and the board of trade, used a broader definition of business, and more recent research.

Dan Larner, executive director of the St. Marks Area Main Streets, said that the two studies complemented each other well.

"[The UMass study] mostly plots businesses and gives statistics on the businesses themselves, while [the Avenue Project's analysis report] also goes into demographics of the neighborhood, gets into a bigger picture, and puts businesses in the context of the whole community," said Larner. He added that the new study was particularly useful for drawing a connection between local businesses and the earning power of residents in the same area.

"Income has a lot to do with the success of a business district and what kinds of businesses you have,' said Larner.

To that effect, the study found that in 2005, businesses in the Avenue Corridor did nearly $400 million in business, while the spending power of residents in that area was even greater, around $670 million.

Jessica Shumaker, a spokeswoman for the BRA, said the new study would be used to inform the economic development components of the ongoing Avenue Project, which will continue through 2010, and as a resource for Main Streets leaders along the Avenue.

The streetscape redevelopment portion of the Avenue Project is scheduled to clear several major hurdles in the months ahead, as city planners and residents meet at three more community meetings to move a master plan for new traffic patterns into the final planning stages by mid-summer.