The information that we are archiving consists of two repositories, DB2
backups and backup of our Pro/I information.

The information should not change as much as it is.   The repositories grow
daily, and the other backups are consistence on a nightly basis.  We do not
use compression here, due to the information being backed up is not
considerably large. Our archives average around 69 GB nightly.  I just find
it hard how it can have a range of about 500 MB from the low end to the high
end.  We use these archives as our disaster recovery, I am just perplexed on
the range.  If it was a smaller amount, I would not be as concerned, but 500
MB is a big difference.

The information that use to determine how much was archived is taken from
the Activity Log in TSM.   Should I look elsewhere to see if this
information is incorrect?