Year	% gross
1970	17.0703792572021
1971	17.0910701751709
1972	17.4003200531006
1973	17.5800399780273
1974	17.7034091949463
1975	18.2366905212402
1976	18.6968803405762
1977	19.1301593780518
1978	19.7233390808105
1979	20.328670501709
1980	21.0221405029297
1981	21.5330104827881
1982	22.3808002471924
1983	23.0288600921631
1984	23.7371406555176
1985	24.5039596557617
1986	24.7361793518066
1987	24.7653102874756
1988	24.661600112915
1989	24.1962203979492
1990	24.4128704071045
1991	24.7756805419922
1992	24.415060043335
1993	24.5828495025635
1994	25.0341796875
1995	25.8681907653809
1996	26.2008209228516
1997	26.319450378418
1998	27.1694602966309
1999	27.4339294433594
2000	27.6038208007812
2001	28.6110305786133
2002	29.2799606323242
2003	29.8828105926514
2004	31.3059501647949
2005	32.3016395568848
2006	33.8707008361816
2007	35.3495903015137
2008	36.856819152832
2009	38.0400314331055
2010	39.0324783325195
2011	39.740421295166
2012	40.8060302734375
2013	41.7627487182617
2014	42.6169509887695
2015	42.6308517456055
2016	42.7814483642578
2017	43.0907287597656
2018	43.1938400268555
2019	43.437198638916
2020	43.8021202087402