How much does Fairfax County Public Schools spend on its central office? How much could be saved and spent on classrooms instead?

Those are central questions in the race for school board this fall, and they can get complicated. Voters have written me asking for answers grounded in data. Here’s a snapshot of what I’ve found.

Many candidates have expressed hope — and sometimes certainty — that the next school board will be able to cut enough fat from Gatehouse to pay for popular initiatives such as reducing class size and raising teacher pay.

Is that possible?

It depends on how deep the board is willing to cut.

In fiscal year 2011 — last year — the school system spent about $324 million on all central-office expenditures except the bus fleet. That figure, which represents about 15 percent of the school system’s $2.2 billion budget, comes from an analysis by the watchdog group FairfaxCAPS. (The figure including the bus fleet: about $392 million.)

For context, reducing class size by one student would cost about $26 million, according to budget documents.

Giving teachers a 1 percent cost-of-living raise this year cost $17.9 million. Allowing teachers their step increase this year: $40.2 million.

What counts as a “central office” cost?

The FairfaxCAPS analysis includes non-school based employees who work in administration headquarters, such as the superintendent, assistant superintendents and various coordinators and specialists who look after things like the budget, public relations, professional development, special education, and curriculum and instruction.

The analysis also includes something called “centrally managed funds,”which encompass a mishmash of things such as central-office employee benefits and countywide IT systems for finances, human resources and student attendance.

How have central-office expenditures changed over time?

Short answer: Expenditures went up until the recession forced belt-tightening.. The proportion of non-school-based positions in Fairfax (7.0 percent of the school system’s total) is now slightly lower than the proportion in Montgomery County (7.6 percent), according to the Washington Area Boards of Education guide.

Here are a series of hamhanded graphs (I’m still learning this blogging business) meant to give a visual sense of changes in the last seven years.

Data source:

The next graph shows how over the same period, enrollment grew by about 7 percent.

Data source: FCPS budgets.

FCPS officials point out that the number of central-office employees has actually dropped in recent years, but costs continue to rise largely because of the increasing cost of employee salaries and benefits — especially health-care coverage.

School system officials emphasize the average annual growth of the budget — about 5 percent — rather than the cumulative growth of a number of years.

Number of central-office employees over time:

Data source: FCPS FY 2012 Approved Budget.

A caveat.

The discussion above is about the school system’s $2.2 billion operating budget — the big pot of money, mostly local tax dollars, that pays for the bulk of the school district’s programs.

FCPS also oversees other pots of money, such as the food and nutrition services fund (the self-sustaining school-meal program); the grants and self-supporting fund (positions paid for by state and federal grants); and the school construction fund (paid for through the sale of general obligation bonds).

The amount of money in each of those pots, and the number of positions paid for out of each pot, can be found on page 27 of the 2012 approved budget.

And lastly, an invitation.

School board candidates, activists, parents and voters: What have I missed? What else should people know about the FCPS budget before Nov. 8? Use the comments section to hash it out.