Grant's post contained the fix for me. His post is as follows.....
"I got in contact with Microsoft and there is a fix for this that requires
an update to the registry to tell Excel 2003 to use the Excel 97 subtotal
method since the new code subtotals incorrectly. I updated my registry and
the subtotaling now works. The registry entry that needs to be added is:
Add the following registry key to -
HKEY_CURRENT_USER\software\microsoft\office\11\excel\options