Hi, I would suggest using the Registrants Report. If participation was marked for attendees, then I would enter the following info under Advanced Criteria (click on Data > Change Report Data) within the report and enter the following under Advanced Criteria.
Field: Participant
Operator: Equals
Value: No
That will show all attendees did not attend. Hope that helps!
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Courtney McLoughlin
Operations Specialist
SolventumUnited States
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