Here's my response as posted in your other, later thread (believe you were
still to resolve the same issues that you posted here) ...
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Let's say you have col data in groups of 3 cols, with headers in row2 (eg:
Period1, Period2, etc), where each header is placed only in the leftmost cell
for the group, eg:

Period1 Period2
9 88 76 6 99 11
1 22 44 5 88 23
etc

To sum the col data corresponding to a specific header (eg: Period1),
you could use* these triplets:
=SUM(OFFSET(A:A,,MATCH("Period1",2:2,0)-1))
=SUM(OFFSET(A:A,,MATCH("Period1",2:2,0)))
=SUM(OFFSET(A:A,,MATCH("Period1",2:2,0)+1))
*placed to avoid circular ref errors, of course

The 1st will return the leftmost col's sum for Period1's group, the 2nd
returns the middle col's sum, and the 3rd returns the rightmost col's sum.
All 3 expressions are similar, where we adjust the OFFSET's col param
returned by the MATCH (that's the: +1,-1 bits) to suit the particular col to
"grab" for the sum. Instead of hardcoding "Period1" in the expressions, you
could of course point to another cell/DV returning the col header for
flexibility. Useful? thump the YES below

--
Max
Singapore
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