The ratio of the number of players in this game to all the teams left after the last swing. If and only if the nature of the competition is elimination system, that is, in the competition system of single defeat elimination system.
That is to say, if it is the top competition of 16, then: 2/ 16= 1/8.
Similarly, Top 8: 2/8= 1/4.
This expression is more widely used in tennis and other competitions with many contestants. The competition is a knockout from the beginning.