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sueshe sueshe is offline
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Default Month End Projection formula?

Thanks Joe, I will work with your answer and see if that fixes my problem. I
had someone else set this sheet up and should have checked everything to make
sure it was right....hind sight ya know!! :) Thanks again!
--
Tasha


" wrote:

sueshe wrote:
Month To Date Days: 8 Days in Month: 30
[....]
total 15
daily avg 1
EOM Proj 22 =dly avg * days in month - mtd days


As I guessed, your error is that when you compute the daily average,
you are truncating the result -- perhaps INT(). This evident by the
fact that you compute 22 for the remainder of the month (1*30 - 8). If
you had used the exact average, you would have computed 48 or 48.25
(1.875*30 - 8). (Which is still wrong!)

Note: In your later posting, you do not show the use of INT() in this
computation. If that is true, then perhaps you have formatted the
cells to show zero decimal places, and you selected the option to
calculate Precision As Displayed (Tools Options Calculation). This
is not advisable in your situation, IMHO. Alternatively, you could
change the format for the Average cell in order to show some decimal
places. Or leave the Average cell as is "for show", but recompute the
exact average in the EOM Proj cell.

But you have another mistake: you are subtracting "mtd DAYS" (8)
instead of "mtd TOTAL" (15). If you had used the latter with your
truncated results, you would have computed 15 (1*30 - 15). (Which is
still wrong!)

The correct computation for EOM Proj is: (15 / 8) * 30 - 15. That is
41.25. You can choose whether to truncate (INT), round (ROUND) or
round up (ROUNDUP) the final result -- but not the intermediate average
-- depending on which makes the most sense for your process. There is
no single right answer. I would tend to round up if the purpose is
predict required resources. Better to predict more than less, IMHO.

If you need help with the precise formulas, feel free to ask. But
looking at your later, you seem to have a good grasp on the Excel
formulation. You simply need to apply some of the corrections noted
above.

HTH.