Hello!
This recently came up as a report request to me, to be able to populate a report based on the ‘External Recipients’ field. However, with it being a comma separated field - moving them to singe lines to get graph type reporting...isn’t a thing.
Looking up another post, I came across “Ability to Report on Internal Attendees from Activity Timeline” in which 
Example:
X attended 3 meetings on their own
	Y attended 2 meetings on their own
	X & Y both attended 1 together. 
	Current output: 
X - 3
	Y - 2
	X, Y - 1
	Desired output:
	X - 4 
	Y - 3
Thank you all!
[It would also be wonderful if on the pivot function in Rules Engine, if we could pivot based on comma-separated fields]