Working on a group project and we've run into a wall on how to account for non-customer/supplier related transactions in inventory (a box of lightbulbs falls off a shelf, an employee drops a glass lamp, etc.) Any ideas how to do this would be appreciated as would any constructive criticism of what we have so far.
TIA

I've left out a few tables intentionally to make fitting everything relevant for this question (mainly 'status' tables.)

use a ReferenceID which links to the special "shrink" reference