I am a manager for a call center of about 150 -175 specialists.  I am looking for others in a call center manager position, to converse with in regards to how you gauge your call center specialists productivity.  Do you use particular metrics (like quality or busy time) and review them on a monthly basis and at what point do you start disciplinary progression?  

We use a "contribution" metric - how much time are you available for customers? - as an indicator to productivity.  As with all metrics, it needs to be validated to ensure behaviors are in line with expectations.  It takes into account expectations for offline coaching time and all other types of "productive and/or required offline" time.   

The tool I was trying lately was Microsoft PowerBI. Maybe it could meet our needs.