Hi Charlie,
Hope you are well!
The report that you ran is 'Registrant Details' from the event homepage which shows the details of the people who have registered for the event. Since you want to show the graph for 'Waitlisted' invitees who have not yet registered for the event, you may try to run the 'Invitee Details' report in the event and then try to edit the graph to display the data. For this please go to your event > Reports > Reports > Report Template > search for 'Invitee Details' report and click on it.
You may also refer to the article for your reference :
Your Guide to Running Reports in Cvent = LINK : : https://support.cvent.com/s/communityarticle/Your-Guide-to-Running-Reports-in-Cvent
I hope this helps. Please do let us know if you have any further questions.
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Raashi Semwal Khati
Senior Quality Analyst
Cvent
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