 After the Second World War, the tournament has taken part annually, with minor exceptions.In most cases, they are round-robin tournaments, where men's groups are of 14-16 players, while the women's are 12 to 14.There were only four Swiss system tournaments in men's tournament history (1975, 1976, 1977, and 1979) and seven in women's (1959, 1965, 1966, 1975, 1976, 1977, 1978).