The following sections describe the formulas that you can enter into the *Copy/Calculate *and *Edit/Match *fields on the Field Description screen.

A formula is a sequence of one or more *statements* separated by a new line or ;. A formula calculates a value that becomes the new value of the field (for *Copy/Calculate *formulas), or is an error message (for *Edit/Match *formulas). Each *statement *calculates a value; the value of the formula is the value of the last *statement *evaluated.

For example, the formula

**quantity * price**

has one statement, an expression, that calculates the **quantity **times the **price.
**

The formula

**if cost >= 100.00
**

"cost must be less than $100.00"

else

""

endif

returns either the string **cost must be less than $100.00 **(if the **cost **field is greater than or equal to 100.00), or the empty string. Since the else part returns an empty string, you can leave it out. The following formula has the same result

**if cost >= 100.00
**

"cost must be less than $100.00"

endif

This example could also be written as

**if cost >= 100.00; "cost must be less than $100.00" endif
**