Vendor Flexfields

We use the PO archive tables to run workbooks against to see committed amounts for specific periods.  This also stores the Vendor ID so we know what vendor was associated with that amount for that period.  But, how can we determine the status of that vendor at that time?  Was it a small business then, even though now it's a large business.  Or data we've chosen to store in a flexflied for vendors.  It could change at a later time, but we need to know what it was at certain periods.  That type of stuff.  Is there anyway to do this?