Section 10 USGA HANDICAP FORMULA
Within each section, all defined terms are in italics and are listed alphabetically in Section 2 – Definitions.
Potential ability is defined by the term Handicap Index and is measured through a calculation using the player’s best scores. These best scores are determined by calculating the Handicap Differential for each score. The Handicap Index is calculated by taking 96 percent of the average of the best Handicap Differential(s), and applying Section 10-3 for players with two or more eligible tournament scores.
A Handicap Differential is computed from four elements: adjusted gross score, USGA Course Rating, Slope Rating, and 113 (the Slope Rating of a course of standard difficulty). To determine the Handicap Differential, subtract the USGA Course Rating from the adjusted gross score; multiply the difference by 113; and divide the resulting number by the Slope Rating. Round the final number to the nearest tenth.
a. Plus Handicap Differential
When the adjusted gross score is higher than the USGA Course Rating, the Handicap Differential is a positive number. The following is an example for determining a Handicap Differential using an adjusted gross score of 95 made on a course with a USGA Course Rating of 71.5 and a Slope Rating of 125:
|Adjusted Gross Score – USGA Course Rating:||95 – 71.5 = 23.5|
|Difference x Standard Slope Rating:||23.5 x 113 = 2655.5|
|Result / Slope Rating:||2655.5 / 125 = 21.24|
|Handicap Differential (rounded):||21.2|
b. Minus Handicap Differential
When the adjusted gross score is lower than the USGA Course Rating, the Handicap Differential is a negative number. The following is an example for determining a Handicap Differential using an adjusted gross score of 69 made on a course with a USGA Course Rating of 71.5 and a Slope Rating of 125:
|Adjusted Gross Score – USGA Course Rating:||69 – 71.5 = -2.5|
|Difference x Standard Slope Rating:||-2.5 x 113 = -282.5|
|Result / Slope Rating:||-282.5 / 125 = -2.26|
|Handicap Differential (rounded):||-2.3|
The Handicap Index formula is based on the best Handicap Differential(s) in a player’s scoring record. If a player’s scoring record contains 20 scores, the best 10 Handicap Differentials of the most recent 20 scores are used to calculate the Handicap Index. As the number of scores in the scoring recorddecreases, the percentage of Handicap Differentials used in a scoring record decreases from the maximum of the best 50 percent. If the scoring record contains 9 or 10 scores, only the best three Handicap Differentials (30 to 33 percent) in the scoring record will be used. Thus, the accuracy of a player’s Handicap Index is directly proportional to the number of acceptable scores posted. A Handicap Index must not be issued to a player who has returned fewer than five acceptable scores. The following procedures illustrate how an Authorized Golf Association, golf club, and computation services calculate a player’s Handicap Index.
The procedure for calculating a Handicap Index is as follows:
Step 1: Use the table below to determine the number of Handicap Differential(s) to use:
Step 2: Determine Handicap Differential(s);
Step 3: Average the Handicap Differential(s) being used;
Step 4: Multiply the average by .96*;
Step 5: Delete all numbers after the tenths’ digit (truncate). Do not round to the nearest tenth.
Example 1: Fewer than 20 scores (11 scores available).
|Total of lowest 4 Handicap Differentials:||104.1|
|Average (104.1 / 4):||26.025|
|Multiply average by .96:||24.984|
|Delete all numbers after |
the tenth digit (truncate).
Do not round to the nearest tenth:
|Handicap Index :||24.9|
* Bonus for Excellence is the incentive for players to improve their golf games that is built into the USGA Handicap System. It is the term used to describe the small percentage below perfect equity that is used to calculate a Handicap Index (96 percent). As a Handicap Index improves (gets lower), the player has a slightly better chance of placing high or winning a handicap event.
Example 2: Twenty scores available. The following is an example of a Handicap Index calculation for a player with 20 scores.