Crossovers - overestimating the graded populations?
Many people rely on PSA and SGC population reports to evaluate the scarcity of a particular card. It’s not a perfect gauge since there are undoubtedly many cards that go ungraded. However, assuming that print runs aren’t released by the manufacturers, it’s probably the most reliable method available.
But, keep this in mind - it’s likely that tallying up PSA and SGC population reports overestimates the population of graded cards. Given aesthetic preferences, perceived differences in value, and a host of other factors, certain collectors prefer one grader over another. When a collector acquires a card in an SGC holder, they may prefer to cross it over to a PSA holder (or vice versa).
Take this 1910 Tip Top Bread Honus Wagner as an example. You can very clearly see that it’s the same exact card. I have a hunch that PSA did not call SGC to let them know that they should reduce their population count by one. And it’s hard to know if SGC removed it from their population since (as of March 2019) you can’t verify a certification number on SGC.
It’s hard to know the level of overestimation. But one thing is certain - unless PSA and SGC figure out a solution, the problem will only get worse.
(And yes, I know that BVG is a player here, but it’s much less common to see pre-war cards in BVG holders).
