total a calculated column in report

[Dsperry101 via AccessMonster.com]

I am constructing a fittings database and trying to calculate the cost of
replacing missing fittings.
I am calcularing the cost of each fitting that needs to be replaced by;
=(([tblFtgs!fldFullStk]-[tblFtgs!fldOnHand])*(
[fldCostPer]))
subtracting the on hand stock (fldOnHand) from required stock (fldFullStk)
then multiplying by the cost for each fitting (fldCostPer).
The problem is , I want a total of all the items needing to be replaced by
summing the column of that calculation but can't get it to work

Trying in a query it says Can't have a Memo , Ole or Hyperlink fields in an
Aggregate object
I get a similar error when trying to sum( the calculated column also tried
Dsum in VBA

Any suggestions ??? Thanks in advance

 

[Ofer Cohen]

In the Report Footer create a text box, and in it ControlSource write

=Sum(([tblFtgs!fldFullStk]-[tblFtgs!fldOnHand])*([fldCostPer]))

The Sum can't be on the name of the text box that holds the formula, the Sum
need to be on the formula itself, or on a field that exist in the table that
the report is bound to