Desktop Support & Helpdesk

Can anyone advise me on the following.
What is the current industry standard for the number of desktop support personal to PC ratio?

What is the current industry standard for Helpdesk Technical calls resolution rate?

I would appreciate soem feedback onthis and would like to hear from anyone who has successfully increased the resolve rate on Desktop problems on tbe Helpdesk and as result decreased the number of people required on the floor. What is the best/preferred mthod of central desktop management.