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Computing Your Index

Ever wondered how your Handicap is figured?  Now you know...

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 or more 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 record decreases the percentage of scores 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 scores (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 authorized golf associations, golf clubs, 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:

Click Here for Handicap Differentials Table

Step 2: Determine Handicap Differential(s);

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; then divide the resulting number by the Slope Rating. Round the final number to the nearest tenth.

Handicap Differential = (Adjusted Gross Score - USGA Course Rating) x 113 / Slope Rating

 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

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 digits after tenths: 24.9

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.

Total of 10 lowest Handicap Differentials: 154.8

Average (154.8 / 10): 15.48

Average multiplied by.96: 14.861

Delete all digits after tenths: 14.8

Handicap Index: 14.8

Step 6: Apply Section 10-3 for players with two or more eligible tournament scores.

Click Here for Two or More Eligible Tournament Scores Table 



 
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