Year	% gross
1970	100.594268798828
1971	102.464790344238
1972	104.076263427734
1973	104.303871154785
1974	104.506309509277
1975	106.012222290039
1976	105.410049438477
1977	104.737983703613
1978	104.069831848145
1979	103.082313537598
1980	102.790031433105
1981	101.615051269531
1982	101.18628692627
1983	102.218109130859
1984	103.234031677246
1985	103.050636291504
1986	102.618667602539
1987	101.872886657715
1988	101.624496459961
1989	101.438667297363
1990	100.787788391113
1991	100.645233154297
1992	101.539527893066
1993	103.666999816895
1994	104.22827911377
1995	104.252326965332
1996	100.234039306641
1997	103.175003051758
1998	101.643943786621
1999	98.4931488037109
2000	97.6672286987305
2001	99.534782409668
2002	100.303993225098
2003	101.312843322754
2004	101.739669799805
2005	101.835731506348
2006	102.123306274414
2007	100.771041870117
2008	101.606239318848
2009	101.833076477051
2010	104.032028198242
2011	104.192237854004
2012	104.007026672363
2013	105.10034942627
2014	105.342628479004
2015	105.365676879883
2016	106.177017211914
2017	107.01806640625
2018	106.787658691406
2019	107.947608947754
2020	106.523643493652
2021	106.687438964844