=COUNTIF($A$1:A1,A1)=1

adapt to your own data and copy down in an adjacent cell will return TRUE
for 1st occurrence

--

Regards,

Peo Sjoblom

"carl" wrote in message
...
I have a series of data like this.

InternalSubcriberRef
30564.00
22222.99
22222.92
30564.00
30564.00
30564.00
30564.00
30564.00
30564.00
30564.00

Would like to add a helper column that will flag the 1st instance of a
given
value.

Thank you in advance.