Schedule count by shift and date...

Hello again,
Here s the deal.... I have a table that describes a weekly schedule of a call center dpt.
For each agent there are several lines, each of one describes by task for an agent (emp id is the key) the start date, the stop date, the start time, the stop time, the assigned task (including breaks...) and the agents team during a day.
As a result there are many lines that describe an agents day shift.

What i am trying to do is to count the number of agents that are assigned to each shift for each team...

I believe that what i need is the earliest assigned task start time and the latest assigned task stop time for each agent for each day....and then count it with date and team (emp class) criteria


any ideas on how to retrieve this out of my original data?...

Thank you all in advance