Forms :: Calculated Controls Based On Weekday In Form

Here is the basic info:

Table has Checkbox column
BusinessDate column (mm/dd/yyyy format)
OrderTotal column (in dollars)
There are others but these are the relevant ones

In the header of the form I have a calculated control box with the following control:

=Sum(Abs(nz([Checkbox],0))*nz([OrderTotal],0)),0)

Which works just fine. The user is presented with a list of all the orders from this table in the form. They check the checkboxes and the control in the header shows the total of the records checked. I need to make 7 of these calculated controls, one for each day of the week. Is this possible? This way the user can see the order totals for each day of the week they have selected.

I tried:
=IIf(Weekday([BusinessDate])=2,Sum(Abs(nz([Pull],0))*nz([OrderTotal],0)),0)

but it still sums up the whole week as the expression holds true.I do not know VB, and I'm sure there is a really neat and easy way to do it in there. I just don't know how.