Year	% gross
1971	9.81645011901855
1972	10.9554004669189
1973	12.2713003158569
1974	12.8253898620605
1975	13.8503398895264
1976	14.9434003829956
1977	15.28297996521
1978	15.7031602859497
1980	19.541410446167
1981	20.2644596099854
1982	21.3402805328369
1983	23.025749206543
1984	23.4141998291016
1985	20.89089012146
1986	21.4026794433594
1987	21.4008693695068
1988	21.3222007751465
1989	22.7066497802734
1990	25.3172302246094
1991	25.3579196929932
1992	30.0771293640137
1993	27.4726295471191
1994	33.6655883789062
1995	35.4894485473633
1996	35.7098503112793
1997	37.4538192749023
1998	39.1929206848145
1999	41.2760391235352
2000	45.9174499511719
2001	46.9373588562012
2002	52.6091117858887
2003	60.0269813537598
2004	66.5821762084961
2005	69.8324279785156
2006	72.9682083129883
2007	73.1370162963867
2008	73.5754699707031
2009	72.4675521850586
2010	78.5030899047852
2011	79.9194183349609
2012	79.5824813842773
2013	78.3723907470703
2014	80.3950881958008
2015	75.6419982910156
2016	74.7006301879883
2017	71.3372497558594
2018	69.3402328491211
2019	70.6093521118164
2020	74.5906066894531
2021	86.5232086181641