Excel - Average last 3 entries

Asked By Preschool Mike on 15-Oct-09 01:48 PM
Can someone help me with some adjustments with this formula that I found in a
search?  I need the formula to average the last three entries in a row, which
it does...it even does an average if there are less than three.. which is
also what I want. But I get an error when there are zero numbers which is
what I want to get ride of.  I found two other suggestions in my search but I
cannot get them to work.

=AVERAGE(INDEX(A4:H4,LARGE(COLUMN(A:Z)*(ISNUMBER(A4:H4)),3)):AB4)
This one works perfectly except I get an error if there are no entries.  I
found the follow two formulas that claim to eliminate the problem but do not
seem to work:

=IF(COUNT(A4:H4)=0,"",AVERAGE(INDEX(A4:H4,LARGE(COLUMN(A:Z)*(ISNUMBER(A4:H4)),4)):H4))


=IF(COUNT(A4:H4),AVERAGE(INDEX(A4:H4,LARGE(COLUMN(A:Z)*(ISNUMBER(A4:H4)),3)):H4),"NEED DATA")


Thanks,
--
Mike Mast
Special Education Preschool Teacher




Gary''s Student replied on 15-Oct-09 02:13 PM
=IF(ISERROR(YOUR_FORMULA),"",YOUR_FORMULA)
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Gary''s Student - gsnu200907
Preschool Mike replied on 15-Oct-09 04:28 PM
Still having trouble.  I get a message that says I have entered too many
arguments.  I have tried entering it exactly how you suggested but not having
any luck.

Here is my formula again
{=AVERAGE(INDEX(A10:H10,LARGE(COLUMN(A:H)*(ISNUMBER(A10:H10)),3)):H10)}

Here is the changes I made as you suggested.  I am sure I have done something
wrong, but what?

{=IF(ISERROR(AVERAGE(INDEX(A10:H10,LARGE(COLUMN(A:H)*(ISNUMBER(A10:H10)),3)):H10),"",AVERAGE(INDEX(A10:H10,LARGE(COLUMN(A:H)*(ISNUMBER(A10:H10)),3)):H10)))}


--
Mike Mast
Special Education Preschool Teacher
T. Valko replied on 15-Oct-09 09:44 PM
it is not real clear what you want to do.

Do you have 0s entered and you want to exclude those 0s from the average?
Are the numbers to average *always* poitive numbers?

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Biff
Microsoft Excel MVP