Hi @Whelan, Stuart
As far as I know, there is currently no direct Microsoft add-on to track the number of responses over time.
Email activity reporting provided by Microsoft 365 admin center has some limitations. You can only understand trends for the last 7, 30, 90, or 180 days. Additionally, you can export report data to an Excel .csv file by choosing the Export link. This will export data for all users and enable you to do simple sorting and filtering for further analysis. More information, see: Microsoft 365 admin center email activity reports - Microsoft 365 admin | Microsoft Learn.
To access email activity reports in Microsoft 365 admin center, go to Reports > Usage page>Exchange > Email activity.
Please kindly understand that many functions are not designed at present. To get this feature more quickly, I have found a post in feedback collection website and you could vote for it. Many features of our current products are designed and upgraded based on customers’ feedback. You can also make suggestions on that website and hope Microsoft will notice this in the future.
Thank you for your understanding and support!
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