Year	% gross
1970	21.9086093902588
1971	22.8228607177734
1972	23.6278495788574
1973	24.5433807373047
1974	26.3177795410156
1975	27.3924903869629
1976	27.7743892669678
1977	28.0297107696533
1978	27.675220489502
1979	27.2690105438232
1980	26.9343490600586
1981	27.415470123291
1982	27.1223793029785
1983	27.5612697601318
1984	28.3414096832275
1985	28.984489440918
1986	30.1603908538818
1987	29.5346698760986
1988	30.5840396881104
1989	30.6110801696777
1990	32.2231788635254
1991	34.342041015625
1992	35.6283988952637
1993	65.0460433959961
1994	66.5564575195312
1995	69.7104110717773
1996	73.2016677856445
1997	77.021598815918
2015	98.9614868164062
2016	99.1694107055664
2017	90.9939193725586
2018	87.498649597168
2019	92.3744812011719
2020	91.2996826171875
2021	91.0609893798828
2022	85.6454315185547