handicap races. Listed races also provide their winners and placed horses with "black type" in sales catalogues and their creation was initially left up to each country to regulate. Listed races in Europe are now also regulated by the European Pattern Committee. The current British Horseracing Authority rules state that a race in Great Britain is a Listed race if "in any particular year, it is a flat race which appears as a listed race in the European Pattern Race Book. The pattern system, overseen by the European Pattern Committee, is fluid and the Group status of key races can change. By this method, the Prince of Wales's Stakes at Royal Ascot was upgraded from Group 2 to Group 1 in the year 2000. However, a number of checks and balances are in place which ensure that changes to the Pattern are gradual and evolutionary, thereby giving the racing industry time to adjust. In particular, the current European Pattern Committee "Ground Rules" explicitly state that no race may be upgraded by more than one Group in any one year. Such restrictions can prove troublesome when major new races are launched. For example, the Dubai World Cup, the world's richest horse race, was only given Listed status for its inaugural running in 1996. National Hunt racing in Europe has an equivalent grading system where the races are known as Grade 1, Grade 2, Grade 3 and Listed races respectively. This takes place independently of the European Pattern system above, which applies only to flat races. Hong Kong, China There are 31 Group races held in Hong Kong, China. Group 1: Group 2 - 7 Group 3 - 12 North America In North America, the equivalent are known as Graded stakes races. Unlike in some other countries, handicap races can be included in the North American and Australian grading system; although most graded stakes races in North America and Group races in Australia are conditions races, and handicaps are more often seen in races of lower level, there are still several handicaps that are Grade I or Group 1 races respectively. Influence on breeding The pattern system exerts a huge influence on the bloodstock market, particularly in relation to the stud fee that a stallion can command for covering a mare at stud. This will be dictated almost entirely by the stallion's performances in Pattern races during its racing career. Only the