Year	% gross
1971	0.152860000729561
1973	0.180260002613068
1974	0.17145000398159
1975	0.22945000231266
1976	0.240720003843307
1977	0.235499992966652
1978	0.232500001788139
1979	0.243139997124672
1980	0.254720002412796
1981	0.251040011644363
1984	0.316839993000031
1985	0.345889985561371
1986	0.360289990901947
1987	0.361519992351532
1988	0.397740006446838
1989	0.460649996995926
1990	0.587660014629364
1999	0.733900010585785
2000	1.16361999511719
2001	1.52813005447388
2002	1.82631003856659
2003	2.22536993026733
2004	2.60763001441956
2005	2.75237011909485
2006	3.57231998443604
2007	3.87260007858276
2008	4.2251501083374
2009	5.16466999053955
2010	5.88123989105225
2011	6.90700006484985
2012	6.69251012802124
2013	7.14920997619629
2014	7.10652017593384
2015	7.25552988052368
2016	7.28971004486084
2017	7.05908012390137
2018	6.49163007736206
2019	6.05810022354126
2020	7.24450016021729
2021	6.99700021743774
2022	7.02685022354126