Year	% gross
1971	71.3598098754883
1972	69.9402923583984
1973	71.2989730834961
1974	71.4456176757812
1975	73.5322570800781
1976	75.5932693481445
1977	77.1064987182617
1978	79.0001373291016
1979	81.2286987304688
1980	82.3848876953125
1981	83.9336318969727
1982	85.4558563232422
1983	85.7598190307617
1984	85.6129913330078
1985	86.4107971191406
1986	86.8927917480469
1987	86.4791564941406
1988	86.9008483886719
1989	86.825309753418
1990	86.3726119995117
1991	85.542106628418
1992	84.0471420288086
1994	92.6996307373047
1995	94.9808578491211
1996	97.4241714477539
1997	99.6421813964844
1998	94.0166625976562
1999	95.1209411621094
2000	96.388313293457
2001	98.4826889038086
2002	99.9955825805664
2003	101.835952758789
2004	95.5285873413086
2005	96.9499664306641
2006	97.4231414794922
2007	97.6523208618164
2008	97.6949996948242
2009	99.2110290527344
2010	101.265991210938
2011	102.005760192871
2012	100.343727111816
2013	107.44563293457
2014	106.215660095215
2015	104.879829406738
2016	103.583801269531
2017	104.332946777344
2018	103.515586853027
2019	102.38427734375
2020	101.721809387207
2021	99.5606689453125
