This is total BS!
Come on....does that translate that 80% of retailers' profits are being lost?
No. That means that of the total revenues that were lost in some fashion - i.e., some percentage of what total revenue would have been without various losses - 80% of that lost revenue is the result of theft.
Now I have no idea how they worked out what revenues were lost but should not have been, but assuming arguendo that can be determined, then that is what they mean.