Year	% gross
1970	50.8065414428711
1971	52.2162590026855
1972	53.9277992248535
1973	55.3566818237305
1974	57.8846893310547
1975	59.5769195556641
1976	60.4935989379883
1977	61.7437896728516
1978	62.262939453125
1979	62.9776611328125
1980	63.144100189209
1981	62.5661392211914
1982	63.3711814880371
1983	62.9640808105469
1984	62.0755195617676
1985	60.1394081115723
1986	60.1074104309082
1987	60.8937492370605
1988	60.9138603210449
1989	60.9936904907227
1990	61.1203689575195
1991	62.1448707580566
1992	64.2623977661133
1993	64.4940567016602
1994	64.2783126831055
1995	64.3072967529297
1996	64.0204467773438
1997	61.8381805419922
1998	61.411750793457
1999	62.1353912353516
2000	60.9929618835449
2001	61.7711181640625
2002	64.2718734741211
2003	65.2085723876953
2004	65.494140625
2005	65.1769027709961
2006	66.2031631469727
2007	66.3459701538086
2008	67.634162902832
2009	69.0115509033203
2010	71.3224029541016
2011	71.8179702758789
2012	70.7437362670898
2013	71.1100463867188
2014	71.498161315918
2015	71.9287185668945
2016	72.092643737793
2017	72.3008804321289
2018	72.510986328125
2019	72.7303009033203
2020	72.7655792236328
2021	72.964111328125
