Hi,

Dates in Column A and what to sum in column B.
This sums data between 2 dates in C1 & C2. Adapt the ranges to suit:-

=SUMPRODUCT((A1:A4C1)*(B1:B4))-SUMPRODUCT((A1:A4C2)*(B1:B4))

"KeK23" wrote:

Does anyone have any ideas on how to calculate data that is listed by date
(not necessarily in date order. I am trying to come up with a week ending
subtotal in a summary sheet from a number of different worksheets. My data
is listed as shown in each worksheet. If anyone could offer a formula to
put in my summary sheet it would be greatly appreciated.

Column b Column I
Date Net weight in tonnes
3/09/2007 37.5