"KCi" wrote:
Is there a way to create the formula so it does not depend on whether or not
the month header in row 1 is filled in? So, it would be strictly based on the
last 12 non-null values in a specific row?

That's a different question.

In Sheet2, to average it for data in say, Sheet1's row11,
you could try, array-entered in say, E2:
=AVERAGE(OFFSET(Sheet1!A11,,MATCH(MAX(IF(Sheet1!$B 11:$IV11<"",COLUMN($B11:$IV11))),IF(Sheet1!$B11:$ IV11<"",COLUMN($B11:$IV11))),,-12))

--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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