Year	% gross
1974	10.216609954834
1975	10.6160001754761
1976	12.4101696014404
1977	15.9998598098755
1978	14.5964698791504
1979	14.7847900390625
1980	15.8706502914429
1981	17.3223495483398
1982	17.6895809173584
1983	18.6723499298096
1984	19.6045093536377
1985	20.9177303314209
1986	22.2476596832275
1987	23.6914100646973
1988	24.5952301025391
1989	24.4928398132324
1990	24.4129009246826
1991	24.204610824585
1992	24.5823993682861
1993	24.7037391662598
1994	24.5526905059814
1995	24.9948806762695
1996	25.4349899291992
1997	23.7594699859619
1998	26.617919921875
1999	27.3428192138672
2000	28.3189907073975
2001	28.8108291625977
2002	28.510440826416
2003	29.549129486084
2004	31.0963592529297
2005	32.6818313598633
2006	35.2790298461914
2007	36.9000205993652
2008	38.6829414367676
2009	40.4342308044434
2010	42.341869354248
2011	45.186450958252
2012	48.4353790283203
2013	50.4754409790039
2014	50.8871307373047
2015	52.7858505249023
2016	54.6001892089844
2017	56.4827995300293
2018	57.470760345459
2019	58.2634086608887
2020	58.5088691711426