The default Style name is Style 1.
To change the default Style:
1. Select Home -> Cell Styles in Styles Group) -> New
2. In Style dialog box click Format.
3. Select the Number tab.
4. In the Category box, select Custom.
5. In the Type box, enter the following format (or change to any desired number formatting):
#,##0;[Red]-#,##0;0;@ (or any other custom number formatting chosen)
6. Select the Font tab.
7. Select a font and the desired font size, and then click OK.
Note: This only changes the Style1 style for the current workbook.
The applications/code on this site are distributed as is and without warranties or liability. In no event shall the owner of the copyrights, or the authors of the applications/code be liable for any loss of profit, any problems or any damage resulting from the use or evaluation of the applications/code.