One thing this report lacks is totals. Since we are showing sales figures on a month-by-month basis, we really ought to show totals for each company.
Switch the report back to Design view.
Add a new textbox into the CompanyName Footer . Call it txtCompanyTotal .
Change the label of the new text box to Total :
Put the following in the Control Source for the new field:
Switch to Preview mode:
How It Works
You've seen the use of functions in fields, and Sum is just another function. When sum is used on a group footer, the argument you give it is the name of the field in the Detail Section . In our case this is SumOfQuantity - that's the field from the underlying query. All Sum does is sum up the values for the field in the Detail Section . It's as simple as that.