All events prior to 2008 had been 16-team events. The first event featured 6 teams from Europe, 3 from South America, 2 from Africa, 2 from Asia, 2 from North and Central America, and 1 from Oceania. Since 2012 it includes 24 teams which split to a six group round-robin tournament, with four teams in each group. The top two teams in each group, together with the 4 highest-ranked third-place finishers, advanced to a sixteen team knockout final series.