Chesapeake D
what a rating means
100 is the average runner in the athlete's pool;
a rating of 133 means 33% faster than that average runner.
Ratings are distance-normalised and course-adjusted, so a hard
course and a fast track land on one number. Each pool (high
school boys, college women, middle school…) has its own
average, and the HS-equivalent view puts every pool on the
high-school scale.