Here's what I came up with...

According to my records there have been 509 collectors who have bought a chip for at least $100 over the past 15 months, and 49 collectors who have bought a chip for at least $1,000 over the past 15 months.

I was amazed that the numbers were so high. I think that the perception is that the "high end" of the hobby is the realm of the precious few with deep pockets, yet there have been about 50 collectors who at least dabble at that level on eBay, and probably many more at the conventions and at live auctions.