How to Measure Average Handling Time (AHT)

Average Handling Time is a key metric in any contact centre. So how do you measure it?

Why is Average Handling Time Important?

Average Handling Time (AHT) is a key measure for any contact centre planning system, as it tells you how long a new item of work takes to be handled, and not just the talk time.

In essence, it tells you how much time an advisor spends working on a task and when they are unable to deal with a new work item.

It is the bedrock for all contact centre planning systems, as well as a key component of all Erlang calculations, and unless you know this metric you cannot plan effectively.

For more on the topic of Erlang calculations, read our article: How to Work Out How Many Staff You Need in a Contact Centre

The Average Handling Time Formula

The formula for calculating AHT is as follows:

$$Average Handling Time = \Large{ \frac {(Total Talk Time + Total Hold Time + Total Wrap Time)}{ Number Of Calls Handled}}$$

Wrap-up time may also be known as Wrap Time or After-Call Work time.

Worked Example

All of the following data can be pulled from the contact centres Automated Call Distribution (ACD) system or, failing this, can be gathered from Call Detail Records (CDRs).

The data used in the example below, is the accumulation of all the length of all calls throughout one day in the contact centre.

Total Talk Time:  7 days + 17 hours + 36 minutes + 45 seconds = 668,205 seconds
Total Hold Time: 1 day, 3 hours + 32 minutes + 33 seconds = 99, 153 seconds
Total Wrap Time: 2 days, 7 hours +5 minutes + 6 seconds = 198,306 seconds
Number of Calls Handled: 4311 calls

If your ACD system produces an average figure for total talk time, total hold time and total wrap time, there is no need to divide the sum of the figures by the number of calls handled.

Average Handling Time is Different from Average Call Duration

Ring time and queue time are not usually included in AHT, as these are not related to the period of time that an advisor spends on a call. They are normally included in Average Call Duration.

What Shouldn’t be Included in Average Handling Time

Contact centres often misuse AHT by including the time that it takes advisors to do things – like toilet breaks, special projects and team meetings – in their calculations.

However, AHT only takes into account the time from when the caller gets through to an advisor until they have hung up. Everything else, including the examples given earlier, should be included in shrinkage calculations.

To find out everything that should be included in shrinkage calculations, read our article: How to Calculate Contact Centre Shrinkage

Factors That can Distort AHT

There are a number of factors that can distort AHT:

Cutting off Callers

If you target advisors on their AHT you may find that they cut off long callers or, if a call looks difficult, they may transfer it to another department.

In fact, there are a number of tricks that some advisors play, such as sitting on a call transfer, hiding behind a IT problem and calling their own phones.

To learn all of the tricks of the trade, which may be impacting call duration, read our article: 7 Tricks That Call Centre Employees Play

Wrap Time Efficiency

Wrap-up time should only be used for time related to the particular call. However, some advisors will use this to stop taking the next call, and it is frequently misused for toilet, coffee or cigarette breaks, or for chatting between calls.

Yet, it isn’t only the contact centre team who may be at fault here, slow computer systems are a likely culprit, which certain advisors may be better at navigating than others.

Whether or Not Hold Time is Included Calculations?

You need to make sure that you include Hold Time in the calculation, as not doing so can result in advisors spending more time on hold in order to reduce the total AHT.

This can negatively impact the customer if they are put on hold unnecessarily at multiple points during the call.

Factors That Drive up AHT

If your AHT is higher than it should be, there are a number of factors that could be to blame:

• Slow computer systems (this is a common problem)
• Spending time with a caller to resolve a problem (this is a good thing)
• Poor advisor training (listening to advisors who have long handling times may highlight individual training needs)
• Flipping between lots of different computer systems
• Long periods of time on hold

Use of AHT as a Performance Metric

Many contact centres use AHT as a personal advisor target as well (in fact, in a number of surveys, it is consistently cited as the most common metric in contact centres) although this is normally deemed a ‘bad thing’.

The problem is that it tends to (either intentionally or unintentionally) make advisors focus on speed of service rather than quality of service. It also tells you nothing about the outcome of a call.

It tends to drive a behaviour of advisors trying to manipulate the AHT.

Symptoms of this include:

• Cutting off calls as they approach the AHT target
• Not doing after-call work or following up on customers
• Transferring difficult calls to another department
• Rushing the caller off the phone
• Not listening to the caller or building rapport
• Making promises to the caller that are not kept

Companies that have removed AHT as an agent performance metric have often found that, after an initial rise in AHT, the First Contact Resolution rates tend to improve.

AHT is Not Distributed Evenly

Once you have measured your AHT to be five minutes, for example, it would be easy to expect that calls would be distributed around the five minute mark, as follows.

This graph is called a normal distribution, but calls that come into the contact centre are not distributed in this fashion. Instead, they are distributed in the pattern of the Erlang distribution, as shown below.

Knowing this is helpful when calculating the number of advisors needed in the contact centre at a given time. This is because it helps to justify why the Erlang C Calculator may seem to overstaff for low call volumes.

To meet the contact centre’s desired service level, it is important to have the correct number of advisors in place, in any eventuality.  And, as highlighted in the graph above, there will be a few calls that last much longer than the handle time.

Just on of these calls can offset a contact centre, which has foretasted low contact volumes. So, the Erlang Calculator takes such a situation into account when making its calculations.

For more on this subject, read the article: How is Average Handling Time Distributed? It is Not How you Think!

Have we missed anything out in our summary of calculating Average Handling Time?

To find out more on AHT, you can read our articles:

Originally published in February 2014. Recently updated.