There is no proven formula, it all depends on your clubs, balls, luck and common sense. If you are referring to the irons, you will need to take into account the trajectory and stopping power, plus the spin of your balls. With lower trajectory irons, balls land and roll, even more if the green is elevated, as the angle the ball approaches the green is really low, add the spin of the balls. Balls usually stop more when the green is below, but that also depends on the course and the hole itself. Basically, it's a trial- error-luck thing, since you also need to ding to get a good shot, but dinging doesn't guarantee the shot will go where you aimed. A formula can help, but other things are involved. Adding backspin to a shot can subtract yards, especially with high trajectory irons, add/ subtract a few yards more depending on wind speed and direction, and DING or get close to it. That ding can mean a few yards too. Take into account that the more distance to the hole, the longer the wind will affect the shot. It's not the same a 20 mph wind in 50 or 100 yards compared to 200 yards, expect the ball to move and be affected more in 200 yards, thus make a decision to move the arrow more in any direction, or use top/backspin and use less/more distance. Expect some shots that don't make sense even with something that has worked 10 times before, and good luck.