how many tech’s does it take

I work for a School system that has 100 schools. We have about 125 Novell file servers, 12,000 desktop computers and 2000 printers. We have 5 pc service techs and 5 network techs. We also support all the OS’S and any software running on the desktop.Almost forgot we also support all the switches, hubs , wire and fiber runs. I am looking for documentation on how many people it takes to support this type of enviroment, I can tell you from experience 10 is not enough. Can you help me ?