Thanks for your input Nurb4000
I've managed to do something very basic, although using straight SQL, so for any of you interested this is a report calculating the average time to resolve a call in the last 7 days by Engineer.
If i could improve this, it would be to display the value of days/hours in one column as " 1 day, 4hours" but instead here i have a seperate column for each....
Select
[User].DisplayName As [Resolved By],
COUNT(*) As [No of Calls],
Avg(DateDiff(d, ReportProcess.ProcessStarted, ReportProcessStatusHistory.DatePosted)) As [Resolved in DAYS],
Avg(DateDiff(hh, ReportProcess.ProcessStarted, ReportProcessStatusHistory.DatePosted)) As [Resolved in HOURS]
From
ReportProcess Inner Join
ReportProcessStatusHistory On ReportProcess.SessionID = ReportProcessStatusHistory.SessionID Inner Join
ServiceDeskIncidentManagement On ReportProcess.SessionID = ServiceDeskIncidentManagement.session_id Inner Join
[User] On ServiceDeskIncidentManagement.resolved_by_user_id = [User].UserID
Where
ReportProcessStatusHistory.Status = 'resolved' And
ReportProcessStatusHistory.DatePosted >= DateAdd(day, -7, Current_TimeStamp)
Group By
[User].DisplayName