For certain files it is possible to add up particular fields in the highlighted records and display the total on the screen. This is done using the Sum Selection command.
- Highlight the records to be added
- Choose Select>Sum Selection or press Ctrl-=/⌘-=
The highlighted records are summed and the result is displayed.
Tip: On the Mac, if you hold down the option key, the Close button will change to Keep, enabling you to keep this sum around and do another.