Shabbir,
I'm not quite sure what you're trying to do, but to bind any control to a
standard or calculated field, create the query, base your form on the query
(i.e., make the query the form's RecordSource), and set the Control Source of
the control to the name of the field.
If you're trying to store a calculation into a table field, there's no need
to do so. Simply calculate it when you need it.
Hope that helps.
Sprinks