I am using this custom pattern "$#,##0.00" to display negative currency in the following format, -$670.90. I am able to get it in the exported excel. But after exporting when I try to do a sumation, avarage, min etc on the cells of the column, the result is displayed in the pattern ($670.90), but it must be displayed in the former pattern. How can I get this? The pattern of the summation result must be similar to the pattern of the values in each cell of the column.