Counting different values

[rgoubet]

Hi,

I found an old post answering exactly the question I had (how to count
the number of different values in a range). However, I don't understand
how it works:

Assuming your data is in A1:A10, and there are no blanks, the
following array formula (from David Hager) will count the number of
unique items:

=SUM(1/COUNTIF(A1:A10,A1:A10))

Use Ctrl+Shift+Enter instead of Enter.

What does Ctrl+Shift+Enter do? Why doesn't the formula work when I use
Enter? What's the logic behind the formula itself?

Thanks!

Raph

 

[Damon Longworth]

Ctrl+Shift+Enter makes the formula an array formula. Have a look here for a
very good explaination of array formulas with many good examples of array
uses:

http://www.emailoffice.com/excel/arrays-bobumlas.html


--
Damon Longworth

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