I typically don't use calculations in a table - I pefer to just store raw
data in the table. I save the calculations for outputs such as reports. For
the totals, simply create a footer for whatever grouping you want to total.
In the footer, place an unbound text box and from the data source in
properties; go to the expression builder and select the sum function. Inside
the parantheses, click on the field name in the report that you want to
total. Good luck.
