Year	% gross
1971	20.429069519043
1972	22.1333808898926
1975	23.2334308624268
1976	25.1155204772949
1977	26.2784404754639
1978	27.161449432373
1979	27.5208301544189
1980	28.8726806640625
1981	29.2387409210205
1982	29.7756309509277
1983	30.0525207519531
1984	30.2814998626709
1985	30.828929901123
1986	32.1105117797852
1987	31.9093494415283
1988	33.0145416259766
1989	33.2323684692383
1990	35.1747398376465
1991	39.1100616455078
1992	41.6281204223633
1993	44.9627113342285
1994	49.9687881469727
1995	49.6192207336426
1996	50.5512084960938
1997	49.2313499450684
1998	49.0185089111328
1999	49.7549209594727
2000	51.4455718994141
2001	52.9789810180664
2002	54.2512283325195
2003	54.9959297180176
2004	56.7709884643555
2005	58.7895011901855
2006	59.8265113830566
2007	60.3940391540527
2008	61.0170593261719
2009	61.4280090332031
2010	63.7049789428711
2011	75.518798828125
2012	75.8141632080078
2015	80.1601486206055
2016	79.8454895019531
2017	83.2009887695312
2018	83.652473449707
2020	85.1104507446289
2021	88.9542617797852