Try this array formula**.

It will work according to these conditions:

If there are 0 scores entered it will leave the cell blank.
If there are <10 scores it will average whatever scores are available.
If there are =10 and <=20 scores it will average the lowest 10 scores.
If there are 20 scores it will average the lowest 10 scores out of the last
20 scores.

Assumes scores are on row 2.

=IF(COUNT(2:2),AVERAGE(SMALL(INDEX(2:2,LARGE(IF(IS NUMBER(2:2),COLUMN(2:2)),MIN(COUNT(2:2),20))):IV2, ROW(INDIRECT("1:"&MIN(COUNT(2:2),10))))),"")

** array formulas need to be entered using the key combination of
CTRL,SHIFT,ENTER (not just ENTER). Hold down both the CTRL key and the SHIFT
key then hit ENTER.

--
Biff
Microsoft Excel MVP


"birdieman" wrote in message
...
I am trying to select the 10 lowest scores from the last 20(changes weekly)
and average them. What is the easiest way to perform this function.