Year	% gross
1971	0.0706899985671043
1972	0.0803399980068207
1973	0.108910001814365
1974	0.0980100035667419
1975	0.0854199975728989
1976	0.0876400023698807
1977	0.124880000948906
1978	0.0967999994754791
1979	0.127959996461868
1980	0.132159993052483
1981	0.059579998254776
1982	0.0819000005722046
1983	0.099260002374649
1984	0.226119995117188
1985	0.363990008831024
1986	0.464210003614426
1987	0.598020017147064
1988	0.685490012168884
1989	0.744759976863861
1990	0.650179982185364
1991	0.773549973964691
1992	0.842050015926361
1993	0.858590006828308
1994	1.05171000957489
1995	1.04102003574371
1996	1.38882005214691
1997	1.67227005958557
1998	1.72079002857208
1999	1.83800005912781
2007	2.99716997146606
2009	2.89913988113403
2010	2.79053997993469
2011	3.09034991264343
2012	3.6486599445343
2013	4.00373983383179
2014	4.17748022079468
2015	4.13881015777588
2016	3.05084991455078
2017	3.67812991142273
2018	4.36499977111816
2019	5.52064990997314
2020	6.37286996841431
2021	6.50381708145142