typical ratio of users to support staff

We are an educational institution running a Novell based administrative network. We currently have approx 1400 clients and are trying to justify support staff expenditures in a very tight budget and would appreciate any data on what is considered normal in support staff for this type of organization. We currently have 2 network administrators and 2 field hardware technicians. It appears that this is not enough to keep everything running smoothly. Any comments?