Year	% gross
1970	17.5356292724609
1971	17.7175998687744
1972	18.1190490722656
1973	18.4020690917969
1974	18.2963695526123
1975	18.4020900726318
1976	18.4439792633057
1977	18.9393196105957
1978	19.4594192504883
1979	20.1560192108154
1980	21.1467094421387
1981	20.8114109039307
1982	21.6531295776367
1983	22.4434795379639
1984	22.6619701385498
1985	22.528959274292
1986	22.4972801208496
1987	23.1430892944336
1988	23.4038505554199
1989	23.331169128418
1990	23.0287494659424
1991	23.8350791931152
1992	24.4326305389404
1993	24.9708194732666
1994	25.7010402679443
1995	26.7807693481445
1996	27.4006805419922
1997	28.0401306152344
1998	29.195930480957
1999	30.0433807373047
2000	30.9890594482422
2001	32.029411315918
2002	33.0917205810547
2003	34.1944999694824
2004	34.7199096679688
2005	35.4413604736328
2006	36.7010116577148
2007	37.6682510375977
2008	38.8780784606934
2009	40.5795783996582
2010	42.0726203918457
2011	43.114330291748
2012	44.3050384521484
2013	45.0720596313477
2014	45.5602989196777
2015	46.0981712341309
2016	47.2996597290039
2017	47.3588790893555
2018	48.2970008850098
2019	48.3006591796875
2020	48.7293815612793
2021	48.6898994445801