 Complete the following phrase:  The format for the World Championship has been largely unchanged since 1982. It has a knock-out format with 32 players, contested over 17 days ending on the first Monday in May, which is a public holiday in the United Kingdom. Before 1982 there were a number of different formats used for the Championship. In 1980 and 1981, 24 players played in the final stages at the Crucible. The top eight seeds had a bye in the first round while seeds 9 to 16 played in the first round against eight qualifiers. From 1977 to 1979, the first three years at the Crucible, only 16 players reached the final stages, eight seeds playing eight qualifiers in the first round. Before 1980, the final was not always played over a set number of frames- for example, in 