Try this...

Assuming your data starts in A2.

Enter this formula in C2 and copy down as needed:

=AVERAGE(OFFSET(A$2,(ROWS(C$2:C2)-1)*10,,10))

This is what you'll end up with:

C2 = average of A2:A11
C3 = average of A12:A21
C4 = average of A22:A31
C5 = average of A32:A41
etc
etc

--
Biff
Microsoft Excel MVP


"MJ" wrote in message
...
I have spreadsheet with 1000 lines of data, time intervals every minute. I
want to average every ten minutes. Is there a realtively simple way to do
this?