Year	% gross
1970	7.47722005844116
1971	7.48681020736694
1972	7.54616022109985
1973	7.5548300743103
1974	7.53403997421265
1975	7.57611989974976
1976	7.66857004165649
1977	8.01632022857666
1978	8.30338954925537
1979	8.5080099105835
1980	8.6358699798584
1981	8.79191017150879
1982	8.85373020172119
1983	8.88519954681396
1984	8.99699974060059
1985	9.16092014312744
1986	9.27184963226318
1987	9.02960968017578
1988	9.30504989624023
1989	9.46712017059326
1990	9.42477989196777
1991	9.33123970031738
1992	9.15454006195068
1993	9.02968978881836
1994	8.81249046325684
1995	8.93970012664795
1996	8.99435043334961
1997	9.19320011138916
1998	9.49081039428711
1999	9.77068042755127
2000	10.1450796127319
2001	11.0751304626465
2002	11.9137201309204
2003	12.5601396560669
2004	13.0883903503418
2005	13.9308099746704
2006	14.4611797332764
2007	14.8383302688599
2008	15.3395099639893
2009	15.6619901657104
2010	15.913200378418
2011	16.2119998931885
2012	16.1782703399658
2013	16.1014709472656
2014	16.3967399597168
2015	15.9859800338745
2016	15.5755300521851
2017	15.6166400909424
2018	15.6331701278687
2019	15.560079574585