By default, the FireFormatColumn property  is False. The FormatColumn event is fired only if the FireFormatColumn property of the Column object is True. The FormatColumn event lets the user to provide the cell's caption before it is displayed on the control's list. For instance, the FormatColumn event is useful when the column cells contains prices ( numbers ), and you want to display that column formatted as currency, like $50 instead 50. Also, it is useful to use the FormatColumn event when displaying computed cells.