Year	% gross
1971	9.23460006713867
1972	10.6135301589966
1973	10.7504196166992
1974	10.6014003753662
1975	10.8503103256226
1976	10.4194402694702
1977	9.47342967987061
1978	8.87565040588379
1979	9.24835014343262
1980	10.1098804473877
1981	11.3904800415039
1982	12.1427698135376
1983	12.977970123291
1984	13.7239999771118
1985	14.9003200531006
1986	14.7955598831177
1987	16.2450103759766
1988	16.9181499481201
1989	17.4654598236084
1990	18.575159072876
1991	18.9696407318115
1992	20.6369590759277
1993	21.622200012207
1994	22.9489898681641
1995	23.3802394866943
1996	25.0863609313965
1997	26.676399230957
1998	25.7685108184814
1999	26.8948993682861
2000	28.4795207977295
2002	30.0928192138672
2003	29.6298694610596
2004	29.8487606048584
2005	30.8059196472168
2006	31.1727695465088
2007	29.3260402679443
2008	31.5467395782471
2010	27.1541404724121
2011	27.041130065918
2012	27.3493309020996
2013	26.4159107208252
2014	26.7061100006104
2015	25.8914394378662
2016	24.7349605560303
2017	25.8916606903076
2018	27.1366806030273
2019	28.809419631958
2020	31.5464992523193
2021	26.5996608734131