Posted By:
jeff sI figure that coming up with correct numbers is probably impossible.
BUT...perhaps there are ways to get a decent grasp on the numbers.
I've heard estimates that there are ~50 T206 Wagners. This we may have to take as faith, but as more attention has been paid to that card than most others, the estimate is credible.
Surely we can determine how many T206 Wagners have been publicly sold over the course of the last year. Let's say, for the sake of demonstration, that there have been two public sales. Thus, let's generalize to all T206s and say that for every ONE T206 card of a certain player sold per year, there are 25 in existence.
Then, let's say we do a survey for a year, or three months, or something, and figure out how many T206 Malarkeys (or somebody) are publicly sold, including those in sets, lots, etc. Not an easy task, but possible. Multiply that number by 25 and the total is some indication of how many are out there.
Of course there are problems with this type of common multiplier. The first two I can think of are these:
1. Extremely popular & rare cards are traded hands more frequently because of their high value and their consistent collecting interest.
2. Cheap cards are traded hands more frequently because people buy them as parts of lots when they may not really want them (and thus resell, altering the "public sale" numbers), and because they are cheap -- i.e. more people can buy them more often.
To some extent, I would think those cancel each other out.
There are problems with a one-year survey, too, b/c of varying collector interest in different issues, players, and the like, but I would think that using a multiplier from, say, research on T206 green portrait Cobbs may well be applicable to other T206s, or other Cobbs that are not exceedingly rare.