Size of your small business IT staff?

I am the CIO, Network Administrator, and Desktop support person all rolled into one for a 50-person company. The company is heavy into Microsoft products and multi media technology with video conferencing. I love my career her, but sometimes it isoverwhelming. Is this a normal workload or am I understaffed? I am interested in other similar companies, the size of their IT staff and how many end-users they support per staff member