12
Opening the insights tab on an email gives the opportunity to view total unsubscribes, however this number only shows the unique clicks on the unsubsribe button from the email, and not how many that actually unsubscribed from the email.

Using the default subscription center results in a record being created for each marketing list when submitting the default subscription center form, regardless of making a change to subscription.

For example:
Email sent out shows 7 unsubscribes in the overview tab.
Under interactions there is 36 unsubscriptions submitted and 12 submitted.
STATUS DETAILS
Completed
Ideas Administrator

In real-time marketing email insights > delivery and interaction details, you can view profiles that unsubscribed using the particular email, uncluding reasons.