Assuming your date is in B6, run this formula down a helper column
=TRUNC(((B6-DATE(YEAR(B6),1,0))+6)/7) for the absolute week number.

Then either create a pivot table or use the SUBTOTAL function to subtotal by
week number.

If you want more info on the formula above, see this:
http://www.cpearson.com/excel/weeknum.htm

Dave
--
Brevity is the soul of wit.


"Wanna Learn" wrote:

Hello I have a large spreadsheet over 10 thousand lines ... How do I
group the sales by weeks , and I also need the week number of the year.
example I want to group all the sales for Nov 7 2005 to Nov 13 then what
is the week number for Nov 7 2005 thru Nov 13 2005 thank you