Year	% gross
1971	101.430511474609
1972	100.055450439453
1973	99.1397476196289
1974	98.9411926269531
1975	99.8990478515625
1976	100.160781860352
1977	99.5975112915039
1978	99.4058303833008
1979	99.1567077636719
1980	99.1271896362305
1981	98.9408264160156
1982	103.714691162109
1983	103.043762207031
1984	102.776123046875
1985	102.575630187988
1986	102.50553894043
1987	102.305458068848
1988	102.272392272949
1989	101.703239440918
1990	102.624122619629
1991	102.14208984375
1992	101.75154876709
1993	101.295059204102
1994	100.988571166992
1995	101.12336730957
1996	101.632522583008
1998	98.3240127563477
1999	98.7224197387695
2000	99.4860916137695
2004	98.9790267944336
2005	98.2066116333008
2006	99.4634628295898
2007	99.4133605957031
2008	98.6847686767578
2009	99.7971420288086
2010	99.39013671875
2011	98.8007125854492
2012	99.6556167602539
2013	99.3787307739258
2014	99.4354705810547
2015	99.5374603271484
2016	97.9061126708984
2017	98.0870208740234
2018	98.3856201171875
2019	97.2296676635742
2020	97.2471237182617
2021	95.9162292480469