How to make a formula to calculate how many of each unique item are in a column in the last 365 days

1

I have two columns A:A (dates) and B:B (items)

..... I need to find a formula to calculate how many of each unique item are in column B : B in the last 365 days. In the example the right value in the formula is 2

Guglielmo Lauro

Posted 2015-05-19T12:29:43.813

Reputation: 11

Answers

1

=count(unique(filter(B:B; A:A > today() - 365)))

The most interesting part is filter(B:B; A:A > today() - 365), which finds all items in 'B' column where there are 'A' column values greater than 365 days ago. Then leave only unique values and count them.

Chupaka

Posted 2015-05-19T12:29:43.813

Reputation: 41

2While this may answer the question, for sake of improving the answer for other who may read it, it would be preferable to include some explanation how it works, why to use it, etc. Referencing a source is also beneficial too. – CharlieRB – 2015-05-19T13:51:06.970