For each campaign, Promoter provides the option to export the survey data from your campaign. Through the export you'll be provided:
Delivery status of the survey
The date of when the survey was sent (dates are in UTC time)
In the 'Status' section of your export is where you can determine which surveys 'bounced/dropped' or were 'unsubscribed' from.
If your export is blank:
Choose a smaller time-frame. There may be too much data for the time-frame chosen and the query is timing out.
No surveys were sent during the time-frame chosen.