[AccessD] Is it possible to change Sub-Totals on Access 2007 Reports with VBA?

We have an Access 2007 report that currently has subtotals by month.

Recently there was a request to create a variation of this report with
subtotals by Customer.

It would be quite easy to create a second report.  But then I remembered
a slogan which said something like "Why make things simple when you can
make them complex and wonderful".  So I started to wonder if it is
possible to use VBA to change a report's sub-totals on the fly
(controlled by buttons at the top of the report).  

Is this possible?

Thanks,

Brad