The easiest way I have found to keep the format in Excel 2003 Pivot Tables is to change the Table options by deselecting the Autoformat Table. I then apply my desired format to the table. Although it takes a little bit longer to format the table, you will find that it no longer reformats when you make changes.
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How to keep the cell borders of the pivot table?
Is there any way to not lose border formatting after refreshing a Pivot
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