The CTR section doesn't do any analysis of the tracking group, but we think this would be useful.  User's in the Tracking group that *would have* seen the bubble would have their CTR calculated so developers could tell what the immediate impact was of users actually seeing the bubble.

Nik wrote:
"For tracking there is no CTR usually, since the IPH is not shown in the tracking group.  Usually it will be 0 for CTR of IPH prompt for tracking group."