Year	% gross
1976	22.0013408660889
1977	22.0054397583008
1978	22.018030166626
1979	22.4881992340088
1980	22.5159397125244
1981	22.4894695281982
1982	22.4562892913818
1983	22.7646903991699
1984	22.9127998352051
1985	23.0243606567383
1986	23.2608203887939
1987	23.1336498260498
1988	23.3676109313965
1989	23.5601196289063
1990	23.6155605316162
1991	25.0599403381348
1992	24.7634506225586
1993	25.7077407836914
1994	25.2664108276367
1995	25.4957408905029
1996	25.9649600982666
1997	26.5147895812988
1998	26.2182502746582
1999	26.5018005371094
2000	26.2529697418213
2001	27.3856296539307
2002	28.336669921875
2003	28.83544921875
2004	29.7663307189941
2005	30.4012508392334
2006	30.6236801147461
2007	31.3745994567871
2008	33.1860809326172
2009	34.2438888549805
2010	34.6273384094238
2011	35.924259185791
2012	35.631649017334
2013	35.8867492675781
2014	37.1484107971191
2015	37.9225807189941
2016	38.147289276123
2017	38.1822204589844
2018	38.9078102111816
2019	38.9975395202637
2020	39.2208290100098