Asa, Aht, Sl

[liviu.pandrea]

Hello everybody
Did anybody knows the mathematical formulas that's calculate ASA, AHT and SL(Average Speed of Answer, Average handling Time, and Service Level) on multiple queues.
For example: If i have 4 queues in a inbound callcentre an ASA is
23,51,0,48 in a day, what is ASA overall/day?
I am asking this because it is not a simple average{(23+51+0+48)/4}and the software that i use don't use the aritmetical average.
Thank you.

[Matt Schmitz]

You need to run a weighted average to compute ASA over several queues. Here's the formula:

((ASA1*calls1)+(ASA2*calls2)+(ASA3*calls3))/(calls1+calls2+calls3)

where ASA1 is average speed of answer on queue 1
and calls1 is number of calls in queue 1

and so forth....

You can use the same formula for SL over multiple queues.

Hope this helps.

Matt

[dwalker]

Absolutely correct - I often see team leaders who simply take an average of multiple averages giving an inaccurate picture of service delivery.

A little Excel tip - use the SUMPRODUCT function for this kind of caluclation (this is probably one of the most useful functions for Call centre staff available).

As an example, if you have three queues with the calls offerred in cells A1, A2, A3; the handle times on each queue in B1;B2;B3; the service levels in C1; C2; C3, then your overall AHT can be calculated as:

=SUMPRODUCT(A1:A3,B1:B3)/SUM(A1:A3)

and your overall service level can be expressed as:

=SUMPRODUCT(A1:A3,C1:C3)/SUM(A1:A3)

hope this helps

Dom