First published by Money Metals here: https://www.moneymetals.com/news/2020/06/29/10-dollar-silver-certificate-value-002066

A $10 bill today doesn’t buy as much as it used to. Yes, indeed… the $10 Federal Reserve Note today would only buy a little more than a half-ounce of silver. However, back in 1934, a $10 Silver Certificate would purchase 18.5 ounces of silver. Try doing that today.