Strokes gained

Strokes gained measures golf performance by comparing the number of strokes a player actually took to complete a hole, or a segment of it, against the average number a benchmark, typically tour-average, player would need from the same starting position. Developed by Columbia Business School professor Mark Broadie, it splits performance into categories: off the tee, approach shots, around the green, and putting, so a player's strengths and weaknesses can be isolated.

For a single shot, strokes gained equals the expected number of strokes to finish the hole from before the shot, minus the expected number from after the shot, minus one for the stroke taken. This differs from simple outcome stats like putts per round or greens in regulation, which ignore how difficult the starting position was; sinking a long putt gains more strokes than a short one, and a poor approach shot can lose strokes even if the resulting putt is made.

Because it accounts for shot difficulty, strokes gained is now the standard way tours and broadcasters break down where a round was won or lost, playing a role similar to shot-quality metrics like expected goals in other sports. It depends on accurate player tracking data and a large reference dataset; results are only as reliable as the benchmark they are measured against, so comparisons across tours or eras with different benchmark populations can be misleading.