Year	% gross
1970	8.61569023132324
1971	8.57896995544434
1972	8.58106994628906
1973	8.50372982025146
1974	8.67516040802002
1975	10.0091199874878
1976	11.5545597076416
1977	12.2648601531982
1978	12.3962697982788
1979	13.4122495651245
1980	13.4861497879028
1981	13.4392004013062
1982	13.7372598648071
1983	13.7010402679443
1984	14.0602903366089
1985	13.3166799545288
1986	13.4358196258545
1987	13.602689743042
1988	13.5646800994873
1989	14.1517000198364
1990	14.3127202987671
1991	14.5337200164795
1992	14.7651901245117
1993	14.406590461731
1994	14.4311895370483
1995	14.4847602844238
1996	15.0281295776367
1997	15.8541097640991
1998	16.2716407775879
1999	16.0914402008057
2000	16.8934497833252
2001	17.3213195800781
2002	18.0664596557617
2003	18.8803100585938
2004	19.6156406402588
2005	20.8673496246338
2006	23.1733303070068
2007	23.4712390899658
2008	24.6973896026611
2009	26.5073509216309
2010	27.2830505371094
2011	27.0686302185059
2012	27.0428791046143
2013	27.2873001098633
2014	30.1411800384521
2015	31.1673393249512
2016	31.2733097076416
2017	31.8105602264404
2018	32.2642288208008
2019	33.3770904541016
2020	33.8311004638672