Formula to calculate unique values between two date ranges

[bdadswell]

Hello;

I have a tab that contains client names in Column "D". There are multiple entries for each client.
Column "A" has the date of entry.

On a separate page, I have a summary page that pulls a lot of other data. On this page is a start date and an end date in cells B4 and B5.

I would like to have a formula that gives me the number of unique clients that are listed in column "D" between the two date ranges.

Any ideas?

 

[Aladin Akyurek]

Hello;

I have a tab that contains client names in Column "D". There are multiple entries for each client.
Column "A" has the date of entry.

On a separate page, I have a summary page that pulls a lot of other data. On this page is a start date and an end date in cells B4 and B5.

I would like to have a formula that gives me the number of unique clients that are listed in column "D" between the two date ranges.

Any ideas?

Let Sheet1 house the data and B4 and B5 on Sheet2 the date criteria.

B6, control+shift+enter, not just enter:

=SUM(IF(FREQUENCY(IF(D2:D50<>"",IF(A2:A50>=B4,IF(A2:A50<=B5,
    MATCH("~"&D2:D50,D2:D50&"",0)))),ROW(D2:D50)-ROW(D2)+1),1))

If there is no risk of having special meaning chars around the name entries, remove the "~"& and &"" bits from the foregoing formula.