Do Principals at schools get a kickback (bonus) for being "under" budget? How can I find this out?

I don't think any school actually manages to be Under budget really but the question might be instead what they do with the budget that they do have as far as how much a principal as well as the teachers are paid. A school will have a certain amount of money in their budget but the question then becomes whether they buy books, computers, sports equipment, or whatever so that while there may not be a kickback as such, shorting the budget in one area would make more money available in a different area, such as payroll and the amount that principal is paid.