Year	% gross
1970	6.42994022369385
1971	10.4724903106689
1972	12.2531604766846
1973	14.0819997787476
1974	15.2268495559692
1975	15.9330196380615
1976	17.8615207672119
1977	19.6935901641846
1978	18.8163394927979
1979	19.6424903869629
1980	20.6902694702148
1981	21.0062198638916
1982	21.5527992248535
1983	20.6340007781982
1984	23.4624996185303
1985	24.1629695892334
1986	26.4895896911621
1987	23.2092304229736
1988	21.1326999664307
1989	20.4084796905518
1990	21.0750694274902
1991	22.8741207122803
1992	24.6114501953125
1993	26.4903202056885
1994	26.2481098175049
1995	28.8332691192627
1996	30.2250995635986
1998	37.7068786621094
1999	39.6028213500977
2000	42.5754699707031
2001	41.6797218322754
2002	40.8190803527832
2003	44.3337516784668
2004	43.1405601501465
2005	41.7703094482422
2006	42.7828216552734
2007	42.9800300598145
2008	43.0983009338379
2009	42.9887313842773
2010	43.9842414855957
2011	41.9725303649902
2012	43.8421783447266
2014	44.9672698974609
2015	47.9322700500488
2016	48.728271484375
2020	45.2206611633301
2021	53.0445899963379
