The index tables set out in the previous versions of the Egyptian system were constructed before the Automatic Handicapping System (AHS) came into being, the Oxford Croquet index table has been implemented to take this into account.  Given that the initial index of a player in an Egyptian is assigned on the basis of that player's handicap, the tables need to reflect any changes in the handicapping system.

In the AHS the player's handicap is adjusted on the basis of the number of games won and lost.  Prior to this system adjustments were made by Handicappers who, primarily, pointed at someone and reset their handicap.

The index tables of Hand's and Carter made a player's Egyptian index approximately a smooth function of the handicap, which at the time was closely related to ability:

The consequences of the AHS are that firstly the spacings between the handicaps have been redefined, e.g. there are now no half handicaps between 5 and 8, and secondly that the 'ability' versus handicap is no longer approximately linear. This was to reflect that a bisque is much more use to an A-class player than a D-class player.  An incidental consequence of the AHS is that someone of the ability of an old 6 now has a handicap of 8.

Under the AHS there is the concept of 'steps'.  The next handicap value is, excepting minus handicaps, one handicap step away from the previous, hence there is one step between 8 and 9.  Above 12 only even handicaps are allowed hence between 16 and 18 is one step, and between 0 and 5 there are half handicaps.  Below scratch (0) there are 2, 3, 3 and 4 steps to -2.  This is how the value of a bisque is adjusted.  A player of 16 is one step away from an 18 but would give 2 bisques,  an 7 would give an 8 one bisque and a 3 would give a 3½,  half a bisque.

Ability is coerced by the AHS into the number of steps difference between the players, consequently the Oxford index table relates AHS steps to the Egyptian index.  This is very easily done!  The AHS uses its own handicap index value - all we have done is made the Egyptian index value equal to 1/10th of that - lop the end zero off.