CALCULATING COMBINED HANDICAP OF A DOUBLES PAIRING FOR HANDICAP AND MIDWEEK CROQUET LEAGUES
Following a successful one year trial by the CA, the method of calculating the Combined Handicap of a doubles pairing, in Handicap Croquet has now been changed. Previously, doubles handicaps were calculated by adding the handicaps of the two players and dividing by two, which favours pairings where one player has a very low handicap and the other has a high handicap. To counter this, the new format totals the trigger index of each player’s handicap, divides that by two and uses it as a trigger point to lookup the combined handicap. This produces the same result as before if players have fairly similar handicaps. The new method, whilst slightly more complex, reduces the bisques formerly given to very low handicap players, so creating a fairer doubles contest. This change has been incorporated into the Laws of the game and so will be used in Federation Handicap Leagues.
To calculate the Combined Handicap of a Doubles Pairing you need to refer to a chart of Handicap Trigger Points (there is one on your Scorecard) and take the following three steps:
(i) Calculate the mean of the pair indexes associated with their Trigger Points.
(ii) Find the nearest Trigger Point with an equal or lower Index.
(iii) Use the Handicap associated with this nearest Trigger Point.
Here is an example for you:
Handicaps: 
Mean Index assoc. 
Nearest 
Combined 

Pair X 
20 and 1 
(950 + 2250)/ 2 = 1600 
1600 
4 
Pair Y 
14 and 10 
(1250+1100)/ 2 = 1175 
1150 
12 
The former system of calculating Combined Handicaps of a Doubles Pairing using mean Handicaps would have resulted in 8.5 for Pair X and 6.5 for Pair Y, i.e. 2.5 bisques difference. The new system based on trigger indexes results in combined handicaps of 4 for Pair X and 12 for Pair Y, i.e. 8 bisques difference. So under the old system Pair Y would get 2.5 bisques but under the new system they get 8 bisques.
Handicap Trigger Points for reference:
HCP: 
24 
22 
20 
18 
16 
14 
12 
11 
10 
9 
8 
7 
6 
5 
4.5 
T.P. 
850 
900 
950 
1000 
1050 
1100 
1150 
1200 
1250 
1300 
1350 
1400 
1450 
1500 
1550 
HCP: 
4 
3.5 
3 
2.5 
2 
1.5 
1 
0.5 
0 
0.5 
1 
1.5 
2 
2.5 
3 
T.P. 
1600 
1650 
1700 
1750 
1800 
1850 
1900 
1950 
2000 
2100 
2250 
2400 
2600 
2800 
3050 
With grateful acknowledgement to the Oxford Croquet website and the CA website.
To simplify the calculations, here is a chart that will do the sums for you:
[gview file=”http://www.croquetnw.co.uk/wpcontent/uploads/2015/03/HandicapDoublesCalculator.pdf”]