If you want to use columns and rows, you can do it this way:

Example --

The weeks are numbered. The entries are made next to their respective
weeks.
The Balance is calculated by a simple formula like =C3+D2
or, if you don't want the balance to calculate when there is a blank in
column C, use =IF($C3="","",INDIRECT("d"&ROW()-1)+$C3)
The calculate the average by using =IF($C3=0,"",$D3/$B3)
Therefore, you would get a table that looked like this below given the
entries in column C

Col B Col C Col D Col E
Weeks Entry Balance Average

1 10 10 10
2 20 30 15
3 30 60 20
4 40 100 25
5 50 150 30
6 60 210 35
7 70 280 40
8 80 360 45
9 90 450 50
10 0 450
11 0 450
12 0 450
13
14


Jack


"lsmft" wrote in message
...

I need a formula for deriving a running average over a period of 52
weeks that will not figure in the zeros for the weeks that have not
arrived. It needs to be a formula that figures only the weeks that have
come to past, as well as, as they come to past. Each week it will change
due to new figures coming for the completed week.
Thank you.


--
lsmft
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