Subtotal when entering data

[SgtBadass]

I've got a form which I can enter data into, a bit like:

Name :Time : Value
Fred 13 34
Jeff 34 66

What I'd like to do is have a subtotal next to the value filed which is updated as the data is entered. I've tried sum(value) but I get the total for the entire table.

Any ideas?

 

[gol4]

Post is not real clear but based on what you describe so far perhaps the dsum() function is what you want

dsum(value,tablename, txt_name = 'Fred')

 

[SgtBadass]

I don't quite understand what the DSum does....

What I've currently got is the first three columns and a user enters the data as below. What I need is for the 'subtotal' column to be populated automatically.

Name :Time : Value : Subtotal
Fred 13 34 34
Jeff 34 66 100
*

I'm guessing I might need a query as well to pull the information, and I was thinking along the lines of Value + previous total = subtotal. But I haven't the foggiest how to do this.

Any ideas?