Year	% gross
1970	5.92179012298584
1971	4.91450977325439
1972	5.03602981567383
1973	5.04528999328613
1974	5.07537984848022
1975	5.94699001312256
1976	6.07508993148804
1977	6.12241983413696
1978	5.41304016113281
1979	5.39229011535645
1980	5.28584003448486
1981	5.40014982223511
1982	5.45693016052246
1983	5.35299015045166
1984	5.42365980148315
1985	5.46081018447876
1986	5.45977020263672
1987	5.48777008056641
1988	5.63536977767944
1989	5.79708003997803
1990	6.18677997589111
1991	6.50972986221313
1992	6.67699003219604
1993	6.93896007537842
1994	7.06829023361206
1995	7.0703501701355
1996	7.651939868927
1997	7.7782301902771
1998	7.89745998382568
1999	7.82365989685059
2000	8.4527702331543
2001	8.92181015014648
2002	9.03680992126465
2003	9.75944995880127
2004	10.3431701660156
2005	10.4329595565796
2006	10.704270362854
2007	11.3913898468018
2008	12.459400177002
2009	13.7124395370483
2010	14.2085399627686
2011	14.9192495346069
2012	15.414119720459
2013	15.6117897033691
2014	15.9318103790283
2015	15.959659576416
2016	15.8059196472168
2017	15.9476699829102
2018	16.0678405761719
2019	16.5852508544922
2020	16.8505001068115
2021	17.2721900939941