Dear Paritosh,
Do you work in a BPO or are you a student trying to find information for an assignment? In either case, it would have saved Dinesh Divekar's time, had you posed the question giving the scenario at the outset.
Had you only searched the web you would have found links such as
How to Calculate Shrinkage in a Call Center | Chron.com at
https://www.google.co.uk/#q=bpo+shrinkage+formula
Hence, I use this opportunity, to appeal to members that we should SEARCH first and then seek clarification by giving the full scenario and what we have already done and found about our query.