Quoted from vid1900:Here is a better example, because we know how many Big Bang Bars still exist:
We know there are ~200 that exist (two have been lost to fire) right now in the world.
61 pinsiders have it in their collections.
So we might guess that for late model games, 1/3 of existing games are listed by Pinsiders.
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So there might be 4000 TZ left in the world.....
I think that's probably on the high side, though. There are a few factors to consider:
1) Most, in fact nearly all, BBBs went to active collectors. Those collectors are much more likely to be active on a site like pinside.
2) A title like BBB is a status pin, so it's more likely a collector would advertise their 'status'. I have a LW3, and until recently had a WCS but didn't list them. Just doesn't matter to me and I gather it doesn't matter too much to others.
I think your conclusion is valid but probably represents the optimistic side of the numbers.