Year	% gross
1971	2.44998002052307
1972	2.2961699962616
1977	12.9273700714111
1978	10.9100103378296
1983	19.3092002868652
1984	20.0760593414307
1987	20.7341995239258
1988	21.9850902557373
1990	21.9702701568604
1999	24.2269897460938
2001	27.2890090942383
2002	28.6147708892822
2003	25.8714408874512
2004	28.4355506896973
2005	28.9930191040039
2007	39.5771598815918
2008	40.3077697753906
2009	43.3568916320801
2010	38.2129096984863
2011	50.1954917907715
2012	48.8520088195801
2013	45.9095993041992
2014	41.4274482727051
2015	49.7663612365723
2016	52.5741386413574