The line graph demonstrates the number of people who joined in including basketball, tennis, badminton, and rugby from 1985 to 2005.
Around 20 years starting at 1985, out of four types of sport, rugby fell sharply, and in contrast to rugby, tennis was raised up. During this period, basketball and badminton were plateauing.
Starting at 1985, rugby had nearly 250 players, at the same time while tennis only had 150 joining. After 15 years, two types of sport had the same data when it had 200 players, but rugby minus 50 joining while tennis plus 50 joining. Fifty players who joined into rugby between 1995 and 2005, this sport plummeted. Although rugby decreased very fast, but tennis increased and maintained over this period.
In 20 years, the number of participants in basketball and badminton did not have unequal numbers of players. Fluctuation in joining numbers approximated 10 to 20 people over 20 years.