Year	% gross
1971	1.95511996746063
1972	2.22551989555359
1973	2.35466003417969
1974	2.6466600894928
1976	3.42625999450684
1978	4.43224000930786
1979	4.88066005706787
1980	4.84181022644043
1981	3.97500991821289
1982	4.44913005828857
1983	3.9781699180603
1984	4.14077997207642
1987	3.51172995567322
1988	3.46082997322083
1989	4.29399013519287
1990	4.27349996566772
1991	4.64940977096558
1992	4.88403987884521
1993	5.26846981048584
1994	5.91664981842041
1995	6.61431980133057
1996	7.18443012237549
1997	7.56509017944336
1998	8.34008979797363
1999	9.66399955749512
2000	11.472240447998
2003	14.2714996337891
2004	16.4488906860352
2005	18.2045097351074
2006	19.6942501068115
2007	22.5880298614502
2008	25.0307693481445
2009	27.7191600799561
2010	30.7705402374268
2011	32.8043594360352
2013	35.5483589172363
2014	36.1575698852539
2015	35.4703598022461
2016	35.1192092895508
2017	35.3535308837891
2018	35.113208770752
2020	32.9609985351562