BREWER – Student enrollments recorded Oct. 1 revealed a total of 1,810 students in Brewer public schools, down 28 from the 1,838 reported on the opening day of school in September.

Superintendent Betsy Webb told the Brewer School Committee on Monday that, over a six-month period, enrollments have been fairly stable, with a net increase of four students compared to April 1 figures.

Key changes since April include a decrease of 26 pupils in kindergarten through fifth grades and an increase of 30 students at Brewer High School.

The city’s preschool program has registered an increase of eight pupils since opening day in September.

Student numbers may change as economic development in the city surges ahead, and a Portland company that specializes in enrollment projections noted that school leaders should closely watch city development to see if it results in an increase of residents living here, as well as an increase in jobs.

The company, called the Planning Decisions Agency, researched school enrollments in Brewer in connection with a long-range plan, approved by the school committee and the trustees, to consider building at least one new school in the city during the next 20 years.

The agency predicted that through the 2013-2014 academic year, the K-5 population would remain stable but that the middle school enrollment may drop by about 50 pupils and the high school enrollment is predicted to drop by 50 students, mostly from areas outside Brewer that send students to the high school.

About 50 percent of Brewer High School’s enrollment is from sending districts outside the city.

“We get students from 20 communities,” Webb told the school committee.