Well, they base range on actual total chances by innings played. Then, they make at least a minor, blankety attempt at adjusting this by era or by strikeout totals in a given season, or something.
Other things besides speed do come into play, such as getting a jump on the ball, quickness, placing oneself in the best place to begin with, precision in getting to the ball and catching it, fearlessness and coordination in discomforting and risky plays, nimbleness to release the ball after it's caught, throwing arm and accuracy....
5/15/2015 12:06 PM (edited)