Forecasting Call Volumes and AHT

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Forecasting Call Volumes and AHT

Any one can help me with forecasting tools for forecasting call volumes and AHT.

I am tired of using the Excel sheet.

Question asked by mitesh

Workforce Management (WFM) Solution

It sounds like you need a Workforce Management (WFM) solution.

It would probably be worth having a look at our Workforce Management Guide.

With thanks to Jonty


It is probably based on our Excel Erlang calculator.

With thanks to Jonty

WFM Tool

All, if you have a standard contact centre with a very reliable call arrival profile, with easily predicted seasonality then a WFM tool could work for you. I have not yet seen a WFM that can handle anything (forecast wise) beyond the basic.

I have used some of the biggest tools out there in my time, and I have always come back to Excel – there is nothing else that you can configure to your EXACT requirements, to deal with all of the nuances of your demand.

WFM tools cannot be beaten for scheduling and exception management (in larger contact centres), but I would suggest a capital outlay of this magnitude just for forecasting is unwise.

Analyse your true demand and do not attempt to overcomplicate your model (spurious accuracy), and don’t give up on Excel just yet.

With thanks to mark2p



I use a spread sheet that times calls by AHT then divides total opening time by a FTE and occupancy

l51 is total calls

m is AHT

3600 is opening time

37.5 is full time agent

$Q$2 is occupancy 75% for us at the moment

With thanks to zoidz

More Information

Zoidz – That formula is correct although:

1. there is an extra set of brackets on the first part doing nothing. (Or two depending how you look at it)

2. That figure won’t have much meaningful value. All it tells you is how many calls an agent could handle if they took calls back to back throughout the whole day. It won’t do you much good for forecasting as calls don’t come in that way. Erlang should really figure in some where.

Also have you excluded breaks from your occupancy, as 75% looks a little high?

With thanks to KevinP


I also use an excel for forecasting call volume and AHT at one of my jobs but at the other I use Vicidial, an open source CRM software that those a lot for me.

With thanks to mirelpopescu


the formula is incorrect as there is no shrinkage (offline time) included in the same.

With thanks to mitesh

Excel Calculator

This is the best spreadsheet to use

With thanks to Jonty

Why FTE Requirement is so Much Higher

Can someone enlighten me why FTE requirement is so much higher when running in the month of Feb than any other months with the same parameters? How does it impact the fact that Feb has only 28 days compared to a 30 or 31 days in other months?

With thanks to girlie

Month Should Not Make a Difference

The month should not make difference on Erlang Calculations as you base it on the calls in one hour.

With thanks to Jonty

Author: Jonty Pearce

Published On: 12th Apr 2022 - Last modified: 21st Apr 2022
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