How is a golfer's expected score determined to create an 18-hole Score Differential™?

Once the player’s 9-hole Score Differential™ has been calculated, it is combined with an expected Score Differential based on the player’s current Handicap Index® to create an 18-hole Score Differential.

The expected score is based on the average Score Differential for a player with a given Handicap Index®, derived from a normal distribution of scores — meaning it reflects a statistical average rather than any individual player's personal scoring history.

An expected score acts as a neutral baseline. This means a strong 9-hole round (relative to the player’s ability) produces a strong 18-hole Score Differential, while an average 9-hole round produces an average 18-hole Score Differential. View the detailed infographic about how expected score is used to create an 18-hole Score Differential.