Sometimes we know how many were made from Chip Order Cards.
But we can only know how many currently exist from observations.
And we cannot observe everything.
For instance, there might only be a handful of highly desirable chips known and they command high value.
It's been that way for a long time and the price has been stable.
But then, we learn that a former employee of the casino was allowed to take home a rack of these chips in a new condition when the casino closed.
The employee recently passed away and his family discovered the chips in a closet and is now selling them.
The rarity of this chip just went from very scarce to readily available.