Here are some metrics to measure your help desk and customer service operation by:
What kind of help desk or customer support organization are you running? As you can see the cost per call is significantly different. This will impact the Return on Investment (ROI) of your help desk or customer support organization. Of course, the strategic stage help desk has the highest customer service and the highest first call resolution rate. Customers also call the help desk or customer service organization less often as the strategic organization has taken many proactive steps to reduce call volume by addressing the root cause of calls to the help desk or customer service organization.
Reprinted from CIO Magazine
Here are two great White Papers on the topic: