In August 2020, with a lot of time on my hands (like many of us then) I wrote a series of three lengthy posts on pricing trends of the Mantle and some other cards since 1953. Some of you may find these to be of interest:
https://www.thetoppsarchives.com/202...es-opener.html
https://www.thetoppsarchives.com/202...for-money.html
https://www.thetoppsarchives.com/202...ng-lights.html