It's interesting that the graph of taxi medallion sales seems to show a trimodal distribution: most sales are close to the market price, but many are consistently at half the market price, and others are much higher, especially during the bubble years.
I think that’s a indicator of an illiquid market, where sales are so few and far between that sale prices are dominated by the specifics of the situation (eg if you can buy three at once, if you can buy that specific day, etc).
Like you might see in rare collectibles eg baseball cards.
What could be the meaning of this pattern?