You can use up and down arrow keys to scroll through the various variable formats in the Variable 
Type dialog box. The types of variables that you can define are: numeric, comma, dot, scientific 
notation, date, dollar, custom currency, and string.

You may also define a variable's width (alt+W) and number of decimal places (alt+P)
within this dialog box. Typically, however, these are pre-set for you.

To save changes and exit the dialog box, hit Tab until the OK button is selected,
then hit Enter.