I am trying to get a cumulative total from numbers being entered in the same cell every week. I have the following worksheet:
First week:
/ A / B / C /
/ 1 / water / cumulative / starting /
/ 2 / 20 / 70 / 50 /

Second week:
/ A / B / C /
/ 1 / water / cumulative / starting /
/ 2 / 10 / 80 / 50

And so on...
I will enter a value in cell A2 everyweek and I want cell B2 to keep a running total.

Thanks for the help. I i didn't explain the good enough, please let me know.

Welcome to the Board!

You need a bit of VBA for that:

Private Sub Worksheet_Change(ByVal Target As Range)
Dim rng As Range
' Only look at single cell changes
If Target.Count > 1 Then Exit Sub
Set rng = Range("A2")
' Only look at that range
If Intersect(Target, rng) Is Nothing Then Exit Sub
' Add A2's value to B2
[B2] = [B2] + [A2]
End Sub

Right click the worksheet tab and select View Code. Paste the code into the module window that opens, then ALT+Q to exit back to Excel.

Type a number into A2 and see what happens.

Hope that helps,

Smitty