Here's the relevant part.
Text Box:
Name: Field1
AfterUpdate: [Event Procedure]
Text Box:
Name: Discount
ControlSource: Discount
4. Set the Field1 field's AfterUpdate property to the following [Event
Procedure]:
Sub Field1_AfterUpdate()
Me!discount = Me!field1 /100
Me!field1= Format(Me!field1 /100, "###.00%")
End Sub
5. Set the form's OnCurrent property to the following [Event Procedure]:
Sub Form_Current(Cancel as Integer)
Me!field1 = Format(Me!discount, "###.00%")
End Sub
HTH