Access Running Total on Form

I have a form with a subform..... the main form shows me the client information (name, address, tel no etc), the subform lists all the orders made for that particular customer.

On the sub form, I want it to perform a running total next to each order, e.g.

Order ID Order Amount Balance
123 £25.00 £25.00
124 £50.00 £75.00
125 £50.00 £125.00

I can do this in a report, but I can't get it to work on a form..... I must be using the wrong calculation.

Any help would be appreciated!!!!

 

ticklyfloss, this is a Major omission by Microsoft's design of Access, they have the running sum in Reports, but not Forms or for that matter Queries either.
It is simple enough to get the overall total using the "Sum" function, but when using a "Continuous Form" a text box will only show the overall total not the Running total for each record.
The attached database has 2 Queries in, one query adds the values in the records to give a running total and the the other subtracts the records from each other.
The SQL code fort the subtraction query was kindly supplied by Jimmy The Hand.
You should be able to modify the Adding Query to supply the data to your form, if you can't I can do it for you.

 

OBP,
That's absolutely fantastic!!!!

Thank you very much!!!