Don't forget to take into account the course conditions and the effects that will help, or hinder back spin. Some greeens due to their slope direction, firmness/softness, moisture content (or lack of), the direction of the grain will impact how much the spin on the ball, will bite, or release. Also, the lie of the ball, and course conditions (wet/dry/grain direction) will have an influence on how much spin can be placed on a ball. GJS