Year	% gross
1970	100.079597473145
1971	100.308029174805
1972	100.261772155762
1973	101.577461242676
1974	101.368469238281
1975	101.212997436523
1976	101.977127075195
1977	102.220336914062
1978	102.097450256348
1979	102.414047241211
1980	104.633056640625
1981	104.772621154785
1982	105.38272857666
1983	105.285026550293
1984	105.708992004395
1985	105.491767883301
1986	105.28491973877
1987	104.943656921387
1988	104.746231079102
1989	104.565780639648
1990	104.978538513184
1991	104.289527893066
1992	104.640830993652
1993	104.659851074219
1994	104.614807128906
1995	104.535118103027
1996	104.27880859375
1997	103.285789489746
1998	104.096076965332
1999	104.016586303711
2000	103.926773071289
2001	103.93302154541
2002	103.977340698242
2003	103.777671813965
2004	103.960540771484
2005	104.010673522949
2006	103.914611816406
2007	103.989860534668
2008	103.942100524902
2009	103.996162414551
2010	103.848243713379
2011	103.630012512207
2012	103.442199707031
2013	103.952751159668
2014	103.125686645508
2015	102.722023010254
2016	102.64688873291
2017	102.066307067871
2018	101.956420898438
2019	102.132820129395
2020	101.333641052246
2021	100.862091064453
2022	100.901252746582