Year	% gross
1971	4.58507013320923
1972	6.42729997634888
1973	7.55612993240356
1974	8.00409984588623
1975	12.8815097808838
1976	18.7777099609375
1977	23.5526790618896
1978	26.9633102416992
1979	26.7333202362061
1980	27.6675491333008
1981	33.2523307800293
1982	35.5787010192871
1983	37.500301361084
1984	38.2598114013672
1985	38.9902992248535
1986	39.4619903564453
1987	37.3991012573242
1988	37.2085914611816
1989	36.9877815246582
1990	37.2837181091309
1991	40.8072319030762
1992	42.5279083251953
1993	42.2552108764648
1994	42.279411315918
1995	43.317310333252
1996	41.9193916320801
1997	44.497989654541
1998	45.9189109802246
1999	44.831241607666
2000	48.5092315673828
2001	50.4489593505859
2002	51.9263000488281
2003	52.8907699584961
2004	54.4264106750488
2005	57.8178787231445
2006	59.7459297180176
2007	61.554759979248
2008	69.130729675293
2009	77.1343078613281
2010	73.462158203125
2011	74.2452163696289
2012	72.9912567138672
2013	76.1131286621094
2014	73.7026672363281
2015	76.1465225219727
2016	70.9093627929688
2017	69.5150680541992