Average of past three months

[Ben]

Hi All,

I'm trying to build a formula to report the average stock
usage over a three month period. I would like the output
to be dynamic so it is always the most recent 3 month
period =TODAY().

The dates are in Column A and they increment on a daily
basis. The amount of stock used on any day is put into
Column B.

Does anyone have any suggestions?

Kind Regards,
Ben

 

[Robert Rosenberg]

Try this formula:

=AVERAGE(IF(A2:A1000>=(TODAY()-90),B2:B1000))

where

A2:A1000 contain the dates
B2:B1000 contain the usage figures

When entering this formula, hold down the CTRL+SHIFT keys to enter it as a
special array type formula.

Note: This formula assumes your "past three months" is "past 90 days."

--
_______________________
Robert Rosenberg
R-COR Consulting Services
Microsoft MVP - Excel
http://www.r-cor.com

 

[Ben]

Thanks Robert... looks good - will try it when I get home
tonight.

Ben