1975 Grand Prix (tennis)
The 1975 Commercial Union Assurance Grand Prix was a professional tennis circuit administered by the International Lawn Tennis Federation (ILTF) which served as a forerunner to the current Association of Tennis Professionals (ATP) World Tour and the Women's Tennis Association (WTA) Tour. The circuit consisted of the four modern Grand Slam tournaments and open tournaments recognised by the ILTF. The Commercial Union Assurance Masters, Davis Cup Final and Nations Cup are included in this calendar but did not count towards the Grand Prix. The men's schedule started in December 1974 with the Australian Open  and continued in May 1975 following the conclusion of the rival 1975 World Championship Tennis circuit which ran from January to early May. Grand Prix points system. The tournaments listed above were divided into four groups. Group TC consisted of the Triple Crown – the French Open, the Wimbledon Championships and the US Open – while the other tournaments were divided into three other groups – AA, A and B – by prize money and draw size. Points were allocated based on these groups and the finishing position of a player in a tournament. No points were awarded to first round losers and ties  were settled by the number of tournaments played. The points allocation – with doubles points listed in brackets – can be found below: ATP Rankings. These are the ATP Rankings of the top twenty singles players at the end of the 1974 season and at the end of the 1975 season, with numbers of ranking points, points averages, numbers of tournaments played, year-end rankings in 1975, highest and lowest positions during the season and number of spots gained or lost from the first rankings to the year-end rankings. List of tournament winners. The list of winners and number of Grand  Prix singles titles won, alphabetically by last number of titles: No players won their first Grand Prix title in 1975.