Hi Robin,
Hope you are well!
You can run the "Agenda Item Registration Overview" report to get the optional item data. For this please go to your event > reports > reports > Search for "Agenda Item Registration Overview" and run the report. Once the data is up, click on Data > Change report data at top right > under selection criteria tab, click on the 'Agenda Item' drop down and uncheck all and only select the 'Quantity Item' option > run the report.
You can also refer to the following article for your reference :
Which report should I run? == LINK : : https://support.cvent.com/s/communityarticle/Which-Report-Should-I-Run
I hope this helps. Please let us know if you have any further questions
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Raashi Semwal Khati
Senior Quality Analyst
Cvent
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