A player’s World Am index is calculated based on your scores from just the previous year. The two lowest differentials are averaged together to create your World Am index. Your two lowest differentials last year were on the 80 and 87 you shot last year where you played 10.3 and 14.8. Using those two differentials your World Am index is 12.5. I hope this is helpful and if you have any additional questions please feel free to give us a call.