Dugtrio [1st Edition] #19
PSA 10 sells for 7.1× a graded 9 ($2,200 vs $311.02).
PSA has given this card a ten 4.2× as often — 11.7% against 2.8%.
How CGC grades work
These are two different pools of submissions, so this compares what each grader did, not what either would do with the same card.