Another thought ..

Assume source data to be averaged is within A1:A20000

Put in B1:
=AVERAGE(OFFSET($A$1,ROWS($1:1)*48-48,,48))
Copy B1 down as far as required to say, B417? to cover the extent of source
data.

B1 returns the average of A1:A48, ie =AVERAGE(A1:A48)
B2 returns the average of the next 48 rows, ie: =AVERAGE(A49:A96)
and so on ..
--
Max
Singapore
http://savefile.com/projects/236895
xdemechanik
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"akoskelo" wrote:
Hi. I have a huge spreadsheet (~20,000 rows). I need to average every 48 rows
into one value. Is there a quick and easy way to do this without scrolling
through all 20,000 rows and copy-pasting the "average" function every 48th
row?

Thank you.