Sum amount at re****t footer is wrong

Dear all,

I have a re****t with the condition like below :

Detail Section :

- EmployeeName
- Salary
- Overtime

Re****t Footer:

= Sum([Salary])
= Sum([Overtime])

Private Sub Detail_Format(Cancel As Integer, FormatCount As Integer)
   If Me.Overtime= 0 Then
      Cancel = True
   End If
End Sub

Sample data :

AAA    1,000    100
BBB     1,000    100
CCC    1,000        0

Output :

AAA    1,000    100
BBB     1,000    100
            -------------
Total     3,000   200

The amount of 3,000 is wrong.
Is there any solution for this problem without change the sql statement
for 
record source ?
Thanks.

Chlaris