To format a number as currency:
Select the Cells command from the Format menu (or right-click and select Format Cells).
Select the Number tab in the "Format" dialog box.
Select Currency from the number list. The "Currency" group box will appear.
The currency symbol will automatically be attached to the number. The rest of the currency options are the same as for the Number format - see Formatting a number for details on how to set these.
You can also use the Currency button to add a currency symbol directly.
Note: The currency symbol used by Ability is taken from the Regional settings in the Windows Control Panel.