"Mike" wrote:
I will have a spreadseet that is approximately 3,000 rows. In Column A, the
user will be entering an account number . There might be 100 unique account
numbers.

I am looking for either a formula or a macro that will automatically display
the unique account numbers as they are being entered. So in this example I
would want the unique account numbers to be listed begining on say row 3010

Perhaps a re-take on the post ..

There's no account# col currently in the source table
and you're creating it now, in col A

Here's one play using non-array formulas ..

Assume source table is in Sheet1,
data in cols B to ?? from row2 down,
and the account#s are being filled in A2 down

In a new Sheet2 (better to do this in a new sheet),

Put in B2:
=IF(Sheet1!A2="","",IF(COUNTIF(Sheet1!$A$2:A2,Shee t1!A2)1,"",ROW()))
Leave B1 empty

Copy B2 down to say B3100
(cover the max expected extent of inputs in Sheet1's col A)

Then put in A2:
=IF(ROW(A1)COUNT(B:B),"",INDEX(Sheet1!A:A,MATCH(S MALL(B:B,ROW(A1)),B:B,0)))

Copy A2 down to say A200
(copy down by the smallest extent sufficient
to cover the max expected # of unique account#s)

Col A will auto-return the list of unique account#s neatly bunched at the top
as the list in col A in Sheet1 is progressively filled in
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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