Completed the challenge.  Added the notification (see attached image) in the Wave developer org.  It looks like it did not save the first time.  Added the notification a 2nd time, as shown in screen capture. 

Can somebody please help me out here how to measure based on the sum of # instead of a count of rows or sum of the amount because on my case # is not appearing on the creating lens window Thanks in advance. PFB more details.
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