Dynamically assign Cell Number

[Guntherm]

Hopefully I can explain this correctly:

Given:
=SUM(IF(FREQUENCY(MATCH($F$2:$F286, $F$2:$F286,0),MATCH($F$2:$F286, $F$2:$F286,0))>0,1))

That tells me if there is duplicates and counts just the unique ones. Works really well(always open to an easier formula)

Here's the issue the $F$2 is static, however in this example $F286 can change(want to change) Based on the last row (Column A) that has data in it.

I have fooled with (ROWS(A:A)-COUNTIF(A:A,"")) which does give me a count of the rows containing data. Any suggestion how to take the value of this formula on this line and incorporate it into above.. or even a better one.[TABLE="width: 163"]
<colgroup><col width="217" style="width: 163pt; mso-width-source: userset; mso-width-alt: 7936;"> <tbody>[TR]
[TD="width: 217, bgcolor: transparent, align: right"][/TD]
[/TR]
</tbody>[/TABLE]
[TABLE="width: 217"]
<tbody>[TR]
[TD="align: right"][/TD]
[/TR]
</tbody><colgroup><col></colgroup>[/TABLE]

 

[Guntherm]

Anyone got a possible direction?

SUM(IF(FREQUENCY(MATCH($F$2:$F&(ROWS(A:A)-COUNTIF(A:A,"")), $F$2:$F286,0),MATCH($F$2:$F286, $F$2:$F286,0))>0,1))

That's what I try and it's a no go. =(ROWS(A:A)-COUNTIF(A:A,"")) into any cells gives me 286 value.