How to Exclude a Case if there is only One Row

Summary: Need to exclude the case if there is only one row.

Content (required): Trying to create a report to display the frequency of response to customers but only if the responses are more than 1. Attached is how the report is currently designed.

Frequency of case responses - an average length of time between analyst responses.

Version (include the version you are using, if applicable): 21D

Code Snippet (add any code snippets that support your topic, if applicable):