Custom Handicapping Mode

Selecting Custom Handicap Mode
Why use Custom Mode?
Why would you ever want to use your own CUSTOM handicapping parameters? Mainly because the USGA calculation procedure calls for a rolling average using the 10 lowest out of 20 score differentials, and you must have at least 5 scores just to calculate a USGA handicap. For clubs that play less than 20 weeks a year, it makes more sense to use a smaller rolling average to handicap golfers. Or maybe your organization does not meet the requirements to issue USGA handicaps. In that case you can set up a custom mode to emulate the USGA system. The calculated handicap would not be an official USGA handicap, but would be very close.
Note: If you use the custom handicapping mode, no Index (Factor for RCGA) will be produced, but a Custom Cdex (analogous to USGA Index and RCGA Factor) along with a course handicap. An Index by definition means you are using the USGA formulas to calculate handicaps.
If you set the Handicap Calculation mode to Custom Handicap the following screen will appear:
To set up handicapping:
Example: If Handicap Percent figure = 90% and a golfer’s Handicap Differentials average is 12, then …
Custom Cdex = 10.8

Note: The more scores a handicap is based on, the less fluctuation you will see in handicaps. In other words, if a golfer’s handicap is based on 20 scores, any new score will have a 1 in 20 (5%) weight on his handicap. However, if his handicap was based on only 4 scores, any new score would have a 1 in 4 (25%) weight on his handicap. 
Note: Many clubs choose to drop some high scores, so that one bad score does not increase a handicap excessively. This helps deter sandbagging. If a golfer shoots an unusually high score, he may think it will make his handicap go up, but in reality it has no effect on his handicap since this high score will be discarded for handicap purposes. The USGA discards high scores to mitigate sandbagging. 
Example: If you want Handicap System to calculate a handicap based on a golfer's last 6 scores, the parameters would be filled in... Number of scores handicap based on: 6 But when a golfer has 6 scores to base a handicap on do you want to drop any high or low scores before calculating a handicap? What if a golfer only has 5 prior scores to look at? Do you want Handicap System to drop any high or low score then? What should Handicap System do if a golfer has only 4, 3, 2, or 1 scores available? You must fill in the table to indicate exactly what you want the program to do in every instance it may encounter.
For example, you may decide on the following… A golfer’s handicap will be based on the best 4 of the last 6 scores shot. If a golfer only has 5 scores, the best 4 of the 5 will be used. If a golfer only has 4 scores, the best 3 of the 4 will be used. If a golfer only has 3 scores, all 3 scores will be used. If a golfer only has 2 scores, no handicap will be calculated. If a golfer only has 1 score, no handicap will be calculated.
The Parameters will be filled out as follows….
According to the table above…

Handicap 
Round 
Truncate 
7.49 
7 
7 
7.50 
8 
7 
7.99 
8 
7 
Custom Handicap Examples
You want to use the best 4 of the player's last 6 scores, and use 90% to determine the handicap. The Parameters will be set as follows:
Handicap Percent(%) figure ..... 90
# of scores handicap based on....6
# of Scores Available 
Discard Highest 
Discard Lowest 
1 
0 
0 
2 
1 
0 
3 
1 
0 
4 
2 
0 
5 
2 
0 
6 
2 
0 
When a player has 1 score, this score will be used for a handicap. (No scores are discarded)
When a player has 2 scores, the lowest 1 will be used for a handicap. (Highest 1 score discarded)
When a player has 3 scores, the lowest 2 will be used for a handicap. (Highest 1 score discarded)
When a player has 4 scores, the lowest 2 will be used for a handicap. (Highest 2 scores discarded)
When a player has 5 scores, the lowest 3 will be used for a handicap. (Highest 2 scores discarded)
When a player has 6 scores, the lowest 4 will be used for a handicap. (Highest 2 scores discarded)
John Smith now has 7 scores entered. What is his handicap? Handicap System calculates the handicap as follows:
Score # 
Used 
Score 
1 
* 
91 
2 
* 
89 
3 
* 
95 
4 

99 
5 

97 
6 
* 
93 
7 

99 
John has 7 scores available. Only the most recent 6 scores are selected for consideration. The best 4 of these 6 scores are used in the handicap calculation. Assume 71.3 is the rating and 115 the slope for all scores. Round differentials to one decimal place (i.e., 10.1, 13.2, etc.).
SCORE 
Differential 

91 
(9171.3) x 113/115 = 
19.4 
89 
(8971.3) x 113/115 = 
17.4 
95 
(9571.3) x 113/115 = 
23.3 
93 
(9371.3) x 113/115 = 
21.3 


 

Sum of differentials 
81.4 
The average differential is determined: 81.4 ÷ 4 = 20.35
Custom Cdex = average differential x Handicap Percent truncated to one decimal place: 20.35 x .90 (handicap % figure) = 18.315 = 18.3
Home course is sloped at 115.
Course Handicap (for home course) = 18.3 x 115 ÷ 113 = 18.62
Course Handicap rounded to whole number = 19
Handicap Example 2
Suppose you want to calculate a simple handicap by averaging the last three scores. How would the CUSTOM HANDICAP parameters be set?
Handicap Percent(%) figure ..... 100
# of scores handicap based on....3
# of Scores Available 
Discard Highest 
Discard Lowest 
1 
0 
0 
2 
0 
0 
3 
0 
0 
Handicap Example 3
Suppose you want to calculate a handicap by selecting 3 out of the last 5 scores. When you have 5 scores you want to drop the high and low scores and use the rest for handicapping. How would the CUSTOM HANDICAP parameters be set?
Handicap Percent(%) figure ..... 90
# of scores handicap based on....5
# of Scores Available 
Discard Highest 
Discard Lowest 
1 
0 
0 
2 
0 
0 
3 
0 
0 
4 
1 
0 
5 
1 
1 
As scores accumulate they would be selected for handicapping as follows:
1 SCORE available  All scores selected
2 SCORES available  All scores selected
3 SCORES available  All scores selected
4 SCORES available  High score dropped, other 3 selected
5 SCORES available  High score dropped, low score dropped, other 3 selected
6 SCORES available  Last 5 considered  High dropped, low dropped, other 3 selected
7 SCORES available  Last 5 considered  High dropped, low dropped, other 3 selected
(and so forth...)
Emulating the USGA formula.
If you want to emulate the USGA handicap system, fill in the form as follows:
Handicap Percent(%) figure ..... 96
# of scores handicap based on....20
Min # scores needed…5
# of Scores Available 
Discard Highest 
Discard Lowest 
5 
4 
0 
6 
5 
0 
7 
5 
0 
8 
6 
0 
9 
6 
0 
10 
7 
0 
11 
7 
0 
12 
8 
0 
13 
8 
0 
14 
9 
0 
15 
9 
0 
16 
10 
0 
17 
10 
0 
18 
10 
0 
19 
10 
0 
20 
10 
0 
The table above follows the exact USGA formula  96% of the best 10 out of 20 scores. Please note that 20 scores are required to produce a full USGA handicap and at least 5 scores are required before an initial handicap is calculated.
You can deviate slightly from the USGA and relax the minimum number of scores required from 5 to 1. This allows you to calculate the initial handicap with only one score. Remember...only the best score out the first 5 or 6 will be used for handicapping. The results will be that handicaps will move only down at first and then handicaps will slowly stabilize.
Handicap Percent(%) figure ..... 96
# of scores handicap based on....20
Min # scores needed…1
# of Scores Available 
Discard Highest 
Discard Lowest 
1 
0 
0 
2 
1 
0 
3 
2 
0 
4 
3 
0 
5 
4 
0 
6 
5 
0 
7 
5 
0 
8 
6 
0 
9 
6 
0 
10 
7 
0 
11 
7 
0 
12 
8 
0 
13 
8 
0 
14 
9 
0 
15 
9 
0 
16 
10 
0 
17 
10 
0 
18 
10 
0 
19 
10 
0 
20 
10 
0 