Why is there a discrepancy between the sum of some historical metrics and another metric in Amazon Connect?

3 minute read

Some historical metrics in Amazon Connect seem like they might add up to equal the value of another metric. However, the sum of the historical metrics and the actual metric don't equal each other.

Short description

Historical metrics in Amazon Connect capture the number of occurrences of an event. Complex formulas that aren't always obvious determine other metrics. Some historical metrics seem like they might add up to equal the value of another metric. However, you might not be accounting for all parts of the other metric's formula.


It's a best practice to view historical metrics and other metrics independently. Don't try to get the metrics to equal each other.

For example, the Contacts queued metric counts the number of contacts that are placed in a queue. Therefore, you might assume that this metric equals the sum of Contacts handled and Contacts abandoned.

Contacts queued = Contacts handled + Contacts abandoned

However, this is incorrect. There are other metrics that make up the formula of Contacts queued:

  • Outbound contacts
  • Contacts transferred out from the queue
  • Callbacks

Outbound contacts

Outbound calls that an agent initiates through CCP aren't counted towards Contacts queued. They're counted towards Contacts handled. Therefore, you must also consider Contacts handled outbound.

Contacts transferred out from the queue

If a contact transfers to another queue within your customer queue flow, then that contact counts toward the following metrics:

  • Contacts queued for the initial queue.
  • Contacts queued for the destination queue.

However, the contact doesn't count toward Contacts handled or Contacts abandoned for the initial queue. The Contacts transferred out from queue metrics for the initial queue count these contacts.


There are many reasons why a callback metric causes a discrepancy:

  • If an agent transfers the contact to a callback queue after it enters the initial queue, then Contacts queued counts this twice. It counts it one time for the initial queuing, and one time for the callback queue.
  • If the callback is set up to use a different queue, then the Callback contacts metric that's used is of the callback queue. The formula doesn't consider the primary queue.
  • If multiple queues use the same queue for callbacks, then Callback contacts for the callback queue include callbacks for all those queues.
  • If you collect metrics when there's a callback pending execution, then the initial contact is counted towards Contacts queued. However, it's not added to Callback contacts yet.

The formula for Contacts queued is similar to the following:

Contacts queued = Contacts handled – Contacts handled outbound + Contacts abandoned + Contacts transferred out queue + Callback contacts

However, even within this complex formula, there are additional discrepancies that you might see. For example, agents might transfer out contacts from a queue to an external party using "Transfer to phone number". There's no metric that captures these contacts. Therefore, it causes a discrepancy between Contacts queued and the sum of the other metrics.

All the preceding examples cause discrepancies in the formula that then cause your values not to exactly add up.

Related information

Historical metrics reports

AWS OFFICIALUpdated a year ago