Year	% gross
1970	21.9693603515625
1971	22.1686592102051
1972	22.7143898010254
1973	23.1094703674316
1974	23.2031898498535
1975	23.8891506195068
1976	24.5905895233154
1977	25.4387893676758
1978	26.5706195831299
1979	27.6716194152832
1980	28.268310546875
1981	28.8914108276367
1982	29.2106399536133
1983	29.4247493743896
1984	29.2985897064209
1985	28.8183002471924
1986	28.3135604858398
1987	27.9723606109619
1988	27.8980293273926
1989	27.2345600128174
1990	26.6289291381836
1991	26.4380702972412
1992	25.8148708343506
1993	25.7161502838135
1994	26.4342803955078
1995	26.614200592041
1996	26.6856899261475
1997	26.8566703796387
1998	27.6952590942383
1999	28.2441291809082
2000	28.7927303314209
2001	29.8935394287109
2002	30.5378608703613
2003	32.3217506408691
2004	34.1529693603516
2005	35.17919921875
2006	37.1245002746582
2007	38.0022010803223
2008	39.8488807678223
2009	41.1460609436035
2010	42.1266784667969
2011	42.860050201416
2012	43.6346015930176
2013	42.6902694702148
2014	43.0325508117676
2015	42.6895790100098
2016	43.1021194458008
2017	43.4379806518555
2018	43.676570892334
2019	43.751148223877
2020	44.058048248291