Order for filtering ratings
1. Must choose “Year” first
2. Must choose “Region” second
Determining how “difficult” a race is
Most people think of a “hard” race as one with difficult terrain or weather. While true, that doesn’t tell the whole story. Instead, think of a “hard” race as one in which it was difficult to place well because a lot of good athletes were there. The average rating of the top-25 highest-rated athletes in each race was used to rank each race highest-to-lowest.
