How to Count Unique Dates based on Criteria

[sillerdu]

Hi,

I have been unable to find an answer to this one. Here is my question, I would like to count the number of unique dates in a sheet based on a criteria. For the example below, I would like to count the number of unique dates for only item F102840.

item	due_date
F102601	4/13/2016
F102650XL	11/15/2014
F102654XL	7/20/2014
F102657XL	10/27/2014
F102658XL	10/2/2014
F102834	10/26/2015
F102840	6/16/2014
F102840	6/24/2014

<colgroup><col><col></colgroup><tbody>
</tbody>

Thanks!!

 

[Rahul1987]

What did you exactly clean up ?
What is the final formula you have applied ?

One way you can modify the formula posted for sillerdu is:

=SUM(IF(FREQUENCY(IF(ISTEXT($A$2:$A15),IF($A$2:$A$15=E1,IF(ISNUMBER($B$2:$B$15),$B$2:$B$15))),IF(ISNUMBER($B$2:$B$15),$B$2:$B$15)),1))

which also must be confirmed with control+shift+enter.

Sir, have you written any book? I am planning to buy one