Examples of performing arithmetic operations in forms, reports, and data access pages

The following table lists examples of expressions that you can use in calculated controls on forms, reports, and data access pages.

If you use this expression	Microsoft Access displays
=[Subtotal]+[Freight]	The sum of the values of the Subtotal and Freight fields.
=[RequiredDate]-[ShippedDate]	The difference between the values of the RequiredDate and ShippedDate fields.
=[Price]*1.06	The product of the value of the Price field and 1.06 (adds 6 percent to the Price value).
=[Quantity]*[Price]	The product of the values of the Quantity and Price fields.
=[EmployeeTotal]/[CountryTotal]	The quotient of the values of the EmployeeTotal and CountryTotal fields.

Notes

In the ControlSource property of a calculated control, precede the expression with the = operator. On a data access page, you can omit the = operator, and type an alias instead; for example, type ExtendedPrice: [Quantity]*[Price].
When you set the Name property of a calculated control in a form or report, or set the ID property of a calculated control on a data access page, make sure to use a unique name. Don't use the name or ID of one of the controls that you used in the expression.
In an expression on a form or report, you can use the name of a control or the name of a field in the underlying record source. In an expression on a data access page, you can use only the name of a field that's in the data definition of the page.
When you use an arithmetic operator (+, -, *, /) in an expression, and the value of one of the controls in the expression is Null, the result of the entire expression will be Null. On a form or report, if some records in one of the controls that you used in the expression might have a Null value, you can convert the Null value to zero by using the Nz function; for example:
=Nz([Subtotal])+Nz([Freight])
For more information on the Nz function, click .