Formula to Calculate Service Level Percentage in Inbound Call Center
Service Level %= (Total Calls Answered within threshold/Total Calls Offerred)*100
Service Level %=(Total Calls Offerred-Total Calls Answered after threshold-Total calls abandoned after threshold)/(Total Calls offered-Total calls abandoned within threshold))
Abandoned after threshold or Within Threshold- This is the calls abandoned within the target time. Some companies do not consider calls which gets abandoned within 10sec or 20 sec. It can be a higher value too.