New York state educators are warning that proposed cuts in state aid to public schools next year could force more than 14,000 teacher layoffs. Officials of the state’s largest teachers’ union claim aid cuts will “devastate” education, leading to a “drastic” reduction of programs and “much larger class sizes.”

But these dire forecasts need to be weighed against a recent growth trend in school staffing. In fact, relative to enrollment, most school districts in New York employed more professional staff last year than they did at the start of the decade. Between 2000-01 and 2008-09, New York schools added 14,746 teachers and 8,655 nonteaching professionals such as administrators, guidance counselors, nurses, psychologists and social workers, according to State Education Department (SED) data. During the same period, statewide enrollment dropped by 121,280 pupils.

The data indicate that nearly half the new staff members were hired in New York City, where Mayor Michael Bloomberg made a reduction in class sizes one of his top priorities after taking office in 2002. The city added 7,072 teachers and 4,042 nonteaching professionals even as its enrollment was decreasing by 62,670 pupils, or 5.9 percent, according to state data.

Upstate schools experienced an even greater enrollment drop of 72,000 pupils, or 7.4 percent, but added 939 teachers and 2,408 other professionals. Public school enrollments in Long Island and the mid-Hudson increased by 1.7 and 1.8 percent, respectively, but school districts in both of those regions increased their teaching staffs by more than 10 percent and their nonteaching professional staffs by more than 20 percent. A regional breakdown of enrollment and staffing data for the period is in the table on the back page.

What accounts for the staff growth? Data from the SED Personnel Master File indicate that roughly half the additional teachers hired statewide between 2000-01 and 2008-09 were in the field of special education, with most others divided among pre-kindergarten, kindergarten and the subject areas of English, science, math and social studies. But the fastest staff growth was in the category of nonteaching professionals, including an added 1,927 principals and assistant principals, 1,149 guidance counselors, 1,107 social workers, 996 psychologists and 992 nurses.

New York City, despite falling enrollment, added nonteaching professionals at nearly twice the rate for other regions.

The data do not reflect school staff reductions implemented through layoffs or attrition since 2008-09. However, the U.S. Bureau of Labor Statistics estimates that total elementary and secondary school payrolls in New York — including both professionals and nonprofessionals — have continued increasing on a statewide basis in the past year.

While class size reduction is a perennial priority of teacher unions, education research indicates that class sizes have little if any impact on pupil performance. Even small reductions in class size are extremely costly; for example, at current enrollment levels, reducing the statewide pupil-teacher ratio by a single pupil would require the hiring of more than 17,500 additional teachers at a cost of roughly $1 billion.

By national standards, class sizes in New York schools were small even before the further staff expansion of the past nine years. As of 2007-08, the most recent year for which comparable statistics are available, New York’s pupil-teacher ratio was 13.1 (down from 13.9 in 2000-01), compared to a national average of 15.5 pupils per teacher (down from 16 in 2000-01). New York’s pupil-teacher ratio was the eighth lowest among 50 states; as of 2007, New York was No. 1 in public school spending, at $15,981 per pupil.

New York City, despite falling enrollment, added nonteaching professionals at nearly twice the rate for other regions.

The data do not reflect school staff reductions implemented through layoffs or attrition since 2008-09. However, the U.S. Bureau of Labor Statistics estimates that total elementary and secondary school payrolls in New York — including both professionals and nonprofessionals — have continued increasing on a statewide basis in the past year.