The ratings started for the 1998-99 season. Every player registered during that season was given a rating of 100.

The system of devising ratings has been refined a few times over the years (so going back to the stats for season 1999-00 to try and work out your new rating for season 2000-01 may not give the same value as shown in the Ratings Archive).

Similarly, from the start of the 2010-11 season, the method of calculating ratings changed to be an average of the last 50 rateable games played, called the R50R (rolling 50-game rating), thus keeping the rating up-to-date and as representative as possible of a players' current standing.

Put simply, how do they work?

Every player gets a game rating for every Singles game played during matches and Singles Competitions, which includes the Open and Silver Singles and the Veterans KO. It used to also include the Captains and Vice-Captains KOs, but will no longer do so now that the format has changed.

The winner of the game gets a game rating equivalent to their opponents R50R plus 50, the loser gets their opponents R50R minus 50.

You can only get a game rating against rated players, you can never get a game rating lower than your own for winning a game, nor can you get a game rating higher than your own for losing a game.

In addition, unrated players cannot get a game rating greater than 50 for a loss.

After every rated game, each player gets an adjusted R50R, being the average game rating of their last 50 rateable games.

If a player has played five or more rateable games (but less than 50), their R50R is partial and is qualified by a 'P'.

Last modified 21-Jun-10