Year	% gross
1970	8.39883041381836
1971	8.7586498260498
1972	9.21450042724609
1973	9.66983032226563
1974	10.2358303070068
1975	11.3159399032593
1976	12.7891998291016
1977	14.0792598724365
1978	15.138279914856
1979	16.6621208190918
1980	17.8438396453857
1981	20.1080303192139
1982	22.8975505828857
1983	25.0918998718262
1984	27.64208984375
1985	29.4085807800293
1986	31.8229503631592
1987	38.6646690368652
1988	39.0938415527344
1989	39.5320816040039
1990	43.2055282592773
1991	41.4725685119629
1992	43.6230010986328
1993	45.3801498413086
1994	46.194881439209
1995	47.9626502990723
1996	49.4175796508789
1997	50.413330078125
1998	51.9322204589844
1999	53.582878112793
2000	54.7588996887207
2001	55.6224708557129
2002	56.1076011657715
2003	57.3975486755371
2004	58.660041809082
2005	60.8990211486816
2006	63.2732315063477
2007	64.8472137451172
2008	67.1839904785156
2009	68.123420715332
2010	73.6195678710938
2011	75.5904006958008
2012	76.4696426391602
2013	70.1430892944336
2014	71.8075866699219
2015	72.7143402099609
2016	73.77734375
2017	75.0678100585938
2018	75.6502838134766
2019	75.6970825195313
2020	75.0323028564453