Clearly, cryptocurrencies usage, apart from pure speculation, is way less than 13% of cash. Isn't it the sign that we are in a giant bubble?
I'm not so sure about that.
I dont see it on the Fed link but the ECB one clearly states that it is about notes and coins in circulation. Cash usage has been constantly decreasing for the past decade compared to electronic payments. Bear in mind that virtually no big payments are made using cash in most countries, like when you buy a house. It would be interesting to know the exact data (cash usage vs electronic cash usage).
What is also clear from that data is that both the FED and the ECB keep printing a lot because physical cash in circulation is increasing while decreasing vs electronic payments.