The calculated data type enables you to resolve simple arithmetic formulae based on single or multiple field values within the current record. The current record may belong to a Relation, thereby enabling you to use fields from different tables in a calculation.
The formatting properties available on the General page are:
Caption (enter a caption to replace the field name above the column in Table View - see Captions)
Index (choose from Primary Key, Indexed, No Index & Indexed (Unique) - see Indexes and primary keys)
The formatting properties available on the Format page are for various types of number, date and time, and the Boolean operator. These determine the format of the answer yielded by the calculated field:
General (the general number format)
Number (see Number format)
Currency (see Currency format)
Percent (see Percentage format)
Fraction (see Fraction format)
Scientific (see Scientific format)
Date and Time (see Date/Time format)
Boolean (use for calculations that return either TRUE or FALSE - see Boolean calculated field)
On the Formula page you can either type in a formula yourself or click on the Function button to display the "Insert Function" dialog, in which you can choose from the standard Ability functions (see Using built-in functions and Using the function dialog box to build formulas for general information on creating functions). Once the formula has been inserted into the Formula box, type in the field names you want to act as arguments for the formula)
See: