Year	% gross
1974	5.65932989120483
1975	6.02759981155396
1976	8.50988960266113
1977	11.3535604476929
1978	9.92665958404541
1979	10.5324401855469
1980	10.9326801300049
1981	13.4152803421021
1982	15.2699203491211
1983	17.2531890869141
1984	17.5201797485352
1985	21.4465408325195
1986	23.8549709320068
1987	24.4810905456543
1988	25.2481307983398
1989	25.4725399017334
1991	25.1081295013428
1992	27.6133098602295
1993	30.411060333252
1994	31.6478691101074
1995	33.8494606018066
1996	33.3066482543945
1997	33.3574600219727
1998	35.8256988525391
1999	34.4313507080078
2000	34.1150016784668
2001	33.8661613464355
2002	34.6695709228516
2003	35.5635108947754
2004	38.3166618347168
2005	38.343318939209
2006	38.2072715759277
2008	43.8650207519531
2009	48.6883392333984
2010	50.4651794433594
2011	51.9342384338379
2012	50.5569000244141
2013	53.122859954834
2014	55.8190803527832
2015	55.3650283813477
2016	55.0438995361328
2017	54.5902481079102
2018	54.6032485961914
2019	53.6006088256836
2020	55.739200592041