Challenge #39: Trouble Shooting a Broken Macro

[AlexC2]

Solution attached, although not sure if the calculation truly reflects the desired retention rate. For example, what happens if the same customer opens an account and closes it in same month? Unless of course, it was intentional to exclude customers that only had accounts for short period of time. 

[jwlong91]

Great challenge to see how batch macros work!

[Ben_Jeffreys]

My submission.

[JethroChen]

Spoiler

[JoePC]

Solution Attached

[mollymargolis]

my solution

[liamholland]

Solution:

Spoiler

[Billigans]

Spoiler

[mollyhatch]

Spoiler

[Tokimatsu]

Solved.