According to “The Age”, Australians have “lost” $8bn in missing banknotes.
Various theories as to where the notes are are floated, including eaten by a pet and drug dealer stashes, etc.
I don’t understand why this problem is not addressed by simply having an expiry date on banknotes - if any can remember the days of cheques, they had an expiry date of one year after which they became “stale”. You could retrieve your entitlement to the proceeds by asking the drawer to cancel it and write another, and this was a fairly regular process.
If we had the same situation with banknotes, expiring at, say, 4 or 5 years, then the holder of a note would need to use it for consumption or attend a bank or other authorized venue such as perhaps the Post Office to have it replaced.
Such replacement would, by it’s nature, enable those who had accumulated the cash legally to get replacements, while the rest would simply lose their black cash forever.
Should a deceased estate cache be found, the money could be re-instated upon satisfactory evidence being presented - just like any other electronic unclaimed moneys.
Legitimate claims for expired note replacement would be paid into the owner’s bank account, not by printing new notes. Very cheap and easy, and forces money out of the cash economy.