Since you need the column index part, ie: AS1
to increment to: AS2, AS3 etc as you copy down from the top cell
think we could use: INDIRECT("AS"&ROW(A1)) in the top cell's formula
The ROW(A1) will act as the incrementer as you copy down

Try this slight tweak to Niek's suggestion:
=IF(I1<J1,100,VLOOKUP(I1,'Male Tables'!$AJ$4:$AT$140,INDIRECT("AS"&ROW(A1))))
Copy down as required
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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"D.Jessup" wrote:
Thank you very much!!! I was dreading the though of having to do a manual
change.

And to answer your question about the AS1 reference. This is correct, it is
yet another function that is used elsewhere on the worksheet.
--
Just an ordinary Joe