Difference fields are used to display the difference between the values of two other data fields, ie. one data field minus the other.

When a Difference field is selected in the field type window, two fields are displayed in the lower half of the window where you should enter the two data fields for which you require the difference. The second data field will be subtracted from the first data field. Each of the fields are selected from a drop down list of all data fields.

Difference fields will automatically be assigned a zero activity number. The two data fields used in the calculation of a Difference field may have any activity number.

At the lowest level of the database, a field set to Difference will display the value of the first data field (Difference1) in the record minus the value of the second data field (Difference2) in the record. At upper levels, a field set to Difference will display the calculated upper level value of the first data field (Difference1) minus the calculated upper level value of the second data field (Difference2).

Wherever a Difference field is used, the component data fields (ie. Difference1 and Difference2) will always be calculated before the Difference field is calculated.