Hi, I too use prize money as an indicator but do it in a much simpler form as part of a system I am currently refining. All I do is divide the total prize money by the number of races to get a minimum average of $3,000 per race. Have found this works particularly well with the younger horses as a quick way of rating the strength of the field. Seems to be particularly useful for mid week meetings as you will often find a much bigger discrepancy between one standout horse and the rest of the pack.