Year	% gross
1971	9.10042953491211
1972	9.57367992401123
1973	9.84140014648438
1974	10.2522897720337
1975	10.7405796051025
1976	10.9554395675659
1977	11.241379737854
1978	11.7538003921509
1979	12.278790473938
1980	13.0379295349121
1981	13.7938404083252
1982	14.8783397674561
1983	16.1608505249023
1984	17.2155704498291
1985	18.8096199035645
1986	20.3598098754883
1987	21.7504291534424
1988	22.2283897399902
1989	23.309009552002
1990	24.2383308410645
1991	25.2738800048828
1992	25.9507999420166
1993	26.7409191131592
1994	27.7635192871094
1995	29.3241405487061
1996	30.8408298492432
1998	33.1966590881348
1999	34.5331687927246
2000	35.630931854248
2001	37.3095512390137
2002	38.4336013793945
2003	40.7949981689453
2004	45.8911590576172
2005	50.4247589111328
2006	54.3220100402832
2007	60.1225891113281
2008	66.324333190918
2009	71.3577194213867
2010	72.9850082397461
2011	76.8712005615234
2012	79.8529205322266
2013	81.9496536254883
2014	83.4542770385742
2015	84.0266189575195
2016	86.4057006835938
2017	88.8005599975586
2018	90.7189788818359
2019	89.4989776611328
2020	88.0442504882812
2021	87.6722793579102
2022	83.3320236206055