Hi,

If that won't work for you, you need to tell us what the thought process
should be for making the estimate. For example, are you assuming that the
monthly sales are the same each year so you can use the prior data to
estimate the future figure. Or are you assuming the the future figures will
be proportional to a prior years results? If you don't have prior data how
can you predict the future?

In other words if you know Jan - Jun what tells you what July's needs might
be?

--
If this helps, please click the Yes button

Cheers,
Shane Devenshire


"JLewis" wrote:

This doesn't work for my data. I tried this approach already. It might work
if each month's sales were fairly equal. The variance between months is too
great. For my example, I got 9.23 when I know the result should be 4.5 or at
its basic using full cells, 5. Thanks for the help though.

"Shane Devenshire" wrote:

Hi,

Suppose last years number are in A1:A12 (Jan-Dec) and your current supply is
in B1

=12*B1/SUM(A1:A12)

--
If this helps, please click the Yes button

Cheers,
Shane Devenshire


"JLewis" wrote:

I have a spreadsheet with current inventory on hand and the sales for each
month from the last year. I want to figure how many months our inventory on
hand will last based on the last years sales. For instance, WidgetA has 100
on hand and Mar, Apr, May, Jun & Jul sales were 5,10,15,40,60, respectively.
I know that we have 4.5 months supply, but I have to manually figure this
calculation. I have more than 400 items. This takes a long time to figure, is
there any way to automate the figuring of the months supply?