Year	% gross
1973	14.1503000259399
1974	14.2850198745728
1975	14.4248600006104
1976	14.519700050354
1977	14.6261596679688
1978	14.9332304000854
1979	15.0705900192261
1980	15.2311000823975
1981	15.090950012207
1982	14.8795003890991
1983	14.7621002197266
1984	14.6592702865601
1985	14.5992403030396
1986	14.8352203369141
1987	15.0868997573853
1988	15.2919397354126
1989	15.354100227356
1990	15.3937501907349
1991	15.3960800170898
1992	15.4355602264404
1993	15.3667497634888
1994	15.173469543457
1995	15.2605895996094
1996	15.5864200592041
1997	15.0602798461914
1998	15.2949600219727
1999	13.2668399810791
2000	14.4989500045776
2001	15.0106601715088
2002	16.3509101867676
2003	17.8317394256592
2004	19.1881008148193
2005	19.8459796905518
2006	21.3009300231934
2007	19.8510303497314
2008	19.6668891906738
2009	21.0285396575928
2010	21.1257591247559
2011	22.9752597808838
2012	26.2657909393311
2013	28.8222808837891
2014	23.6648807525635
2015	25.5439701080322
2016	26.6866607666016
2017	27.1962108612061
2018	27.1243705749512
2019	27.4399108886719
2020	28.1429405212402