THE STATE auditor general's report released last week that revealed the School District has a structural deficit hardly qualifies as big news. It isn't even new.

The words "deficit" and "school district" have appeared next to each other for years. The district has been running a deficit for more than five years. In the past, it was so great that the district had to lay off thousands of workers, close schools, and cut its budget to the bone.

The key word in Auditor General Eugene DePasquale's report is "structural."

A structural deficit isn't caused by a once-in-a-decade incident. It is caused when your expenses always exceed your revenue.

If you are a couple whose combined income is $75,000 a year and your spouse is laid off from her job, you will face a deficit - one that could be remedied if she gets that job back.

If you are a couple whose combined income is $75,000 a year and you spend $80,000 every year, you have a structural deficit. You will have to increase your earnings or cut your expenses.

The situation at the Philadelphia School District is weird. DePasquale didn't exactly use that word, but that's the gist of his report. The district has no control over some of its fastest rising expenses and no control over its income. Its income is decided by others: City Council, the state legislature, the governor and the mayor.

It can adjust spending - as it has over the recent rocky years. But it is legally mandated to meet costs included in contracts with its employees, including pension payments - which are also mandated by state law. Nor does it have much control over the fastest-growing section of its budget: charter-school costs.

Over the next five years, the district's revenue is due to rise 2.6 percent a year while its expenses will rise 4.8 percent a year. Now that's a structural deficit.

Meanwhile, over the next five years, charter enrollment is projected to increase by 19 percent - from 68,000 to 81,000. Charter schools are independent public-funded schools that the district supports with a per-pupil allowance. Next year, the district will spend $752 million in charter reimbursements. Five years from now, it is projected to be spending $1.1 billion.

The district tried to get a handle on charter costs by putting a cap on enrollment, but that method was declared illegal by the courts. It tried to impose new contract terms on teachers, but that was also knocked down by the courts.

DePasquale said something has to be done to remedy this situation. One major step would be for the state to increase its aid to public schools, but Gov. Wolf and the Republicans who control the legislature have been fighting on that issue for nearly two years. He wants to increase taxes to pay for it; they don't.

The legislature could also help by doing something - please, anything! - about our out-of-date charter law. Enacted in 1997, it was built around the idea that charters would be an educational experiment likely to draw a limited number of students.

It was never foreseen that nearly 20 years later we would have 162 charter schools around the state, 86 in Philadelphia alone. A revised law is needed to deal with the modern realities of charter education, and to restore the charter subsidies the state used to give districts to bear the cost of the charter mandate.