As the older cards go those early 70s really havent changed much until last year and they are turning 50 years old. In another 50 years they will double in value because they will be 100 years old just like the T206 and the T205 cards did in 2011. If I am still around in 2033 i expect the goudy double in value and in 2048 the Bowman will double in value
reason for this the cards will be locked up in peoples collections and some will be destroyed by family members, natural disasters and house fires. So every year goes by i bet collections are destroyed. Just how many cards were destroyed in the Texas wildfires. This is one reason older cards have values change
could also reflect like 2014 you could find literally 100’s of 1972 Thurman Munson cards and now you might find only 25 or so on ebay ( didn’t look it up but was trying to give an example)