Let's start with some background. I've been redesigning an application so
that each customer's data is archived as a data file, which can then be
restored to the application, changed, saved again, etc. The data files are
themselves one-worksheet Excel workbooks. Ranges to be archived are
identified by tags in column AP; the tag is also the means by which the
archiving and retrieval applications know what to save and where to restore
it. The application consists of several dozen worksheets, ranging in size
from fifty rows to approximately 1,700 rows. To a considerable extent, I've
been able to write VBA code to hide rows that don't need to be displayed or
printed. In some cases, however, it would be very helpful if a user could
group some rows and hide the detail.

Is there a way for me to save any identification of which rows are grouped
(and at what level) in my data file?