G'day
For Formulas
I my experience it best for backward compatibility is 97-2003 Workbook format.
When you save in 97-2003 format will pick up what can not be shown in older versions.
Eg If you used a SUMIFS formula, on saving document a compatibility box such pop up to tell you the value of the formula will return #NAME.
You can even default Excel 2007 to save in this mode.
This can be found in the Office button > Excel Options > Save > Save files in this format:
I can not see any reason why this should not do the same for macros.
Hope this helps
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