Year	% gross
1970	4.77383995056152
1971	4.7497501373291
1972	4.8717098236084
1973	5.10656976699829
1974	5.47713994979858
1975	5.76331996917725
1976	5.88858985900879
1977	6.09150981903076
1978	6.26015996932983
1979	6.29631996154785
1980	6.23910999298096
1981	6.45456981658936
1982	6.52672004699707
1983	6.61355018615723
1984	6.79617977142334
1985	6.92570018768311
1986	7.01634979248047
1987	6.99288988113403
1988	7.06885004043579
1989	6.98368978500366
1990	6.8399600982666
1991	6.71747016906738
1992	6.46755981445312
1993	6.22901010513306
1994	5.8951997756958
1995	5.72847986221313
1996	5.56772994995117
1997	5.45672988891602
1998	5.57871007919312
1999	5.70734977722168
2000	5.93204021453857
2001	6.20109987258911
2002	6.36467981338501
2003	6.59289979934692
2004	6.9773998260498
2005	7.40209007263184
2006	7.76627016067505
2007	8.10960960388184
2008	8.7010498046875
2009	9.43990039825439
2010	10.0885601043701
2011	10.1893301010132
2012	10.5326595306396
2013	10.7465896606445
2014	11.1592597961426
2015	11.0541000366211
2016	10.814920425415
2017	10.8885297775269
2018	10.9845600128174
2019	11.0778703689575
2020	11.2696304321289