At a certain point, somewhere in the middle ranges of these scores, formal education at even the best schools will stop having any effect on your vocabulary. I

At a certain point, somewhere in the middle ranges of these scores, formal education at even the best schools will stop having any effect on your vocabulary. It becomes more a matter of where someone's interest lies. Do they read? A lot? Outside of the usual curriculum? And at the upper end, it's more about personal predilections than anything else. Are rare words like little gems that you save and collect?