To see the number (or a count) of emails that have unsubscribed in a specific date range, go to Reports, click on List Activity Summary and choose the date range for which you’d like the report. In the report that follows, if there were any unsubscribes in the date range you selected, the Activity Column will have a row for Unsub Request with a number next to it in the Volume column. This is the total number of unsubs that took place for the selected date range.

To view the unsubs for a particular campaign go to Reports and click on Campaign Summary.