This assumes cash transactions are actually recorded. Given the increasingly invasive surveillance of digital transactions, I expect the numbers and reality to diverge more as time progresses.
Also, to be pendantic about it, I've never actually seen someone spend hard cash, just fiat currency, which has much lower value.
I do keep a US Minted dollar handy, should the need arise for hard currency. Made in 1901 at the New Orleans mint
edit/clarify: Yes, a 1901 Morgan Silver Dollar, a coin with a current melt value of $39.64 according to coinflation
the extra value in that bill comes from the collector and historical interest; I'm not sure the US government is really obligated to pay out rare metals for your bill, if that's the distinction you're making.
Anyway, I think we as a society should normalize using silver coins for personal wealth transfer, because they are a good size and weight for not too much value, and they are shiny and make a satisfying jingle sound when kept in a bag
Also, to be pendantic about it, I've never actually seen someone spend hard cash, just fiat currency, which has much lower value.
I do keep a US Minted dollar handy, should the need arise for hard currency. Made in 1901 at the New Orleans mint
edit/clarify: Yes, a 1901 Morgan Silver Dollar, a coin with a current melt value of $39.64 according to coinflation