Year	% gross
1970	17.9619102478027
1971	18.0571994781494
1972	18.55837059021
1973	19.4061107635498
1974	20.2217998504639
1975	21.2243595123291
1976	22.8140296936035
1977	24.7225608825684
1978	26.2892799377441
1979	27.7320003509521
1980	28.9914608001709
1981	30.2113094329834
1982	31.9407291412354
1983	33.3322296142578
1984	34.7523918151855
1985	36.3491516113281
1986	38.2473106384277
1987	39.3461303710938
1988	40.0177917480469
1989	40.8935317993164
1990	43.9336891174316
1991	44.5620002746582
1992	44.4467391967773
1993	45.3749809265137
1994	47.3298187255859
1995	47.9855690002441
1996	48.0002899169922
1997	49.5186004638672
1998	51.4690017700195
1999	53.28076171875
2000	54.7879295349121
2001	56.3731994628906
2002	57.7624816894531
2003	59.7602500915527
2004	61.4247589111328
2005	61.7896003723145
2006	61.8584213256836
2007	60.8792381286621
2008	61.1564903259277
2009	62.6225814819336
2010	63.5329208374023
2011	65.8406677246094
2012	66.5629425048828
2013	65.2073211669922
2014	65.4618988037109
2015	66.4050521850586
2016	66.1366119384766
2017	66.3946380615234
2018	66.8959274291992
2019	67.2155532836914
2020	67.476318359375
2021	68.3140029907227
2022	69.0023727416992