Year	% gross
1971	100.849411010742
1972	100.538429260254
1973	100.047302246094
1974	99.8328475952148
1975	99.5869827270508
1976	99.6859512329102
1977	99.7401885986328
1978	99.621223449707
1979	99.5564193725586
1980	99.9462585449219
1981	100.133148193359
1982	100.536140441895
1983	100.166320800781
1984	99.5654830932617
1985	99.0750122070312
1986	102.427223205566
1987	101.941772460938
1988	101.631660461426
1989	101.397727966309
1990	101.265441894531
1991	101.220802307129
1992	96.7744598388672
1993	96.7115783691406
1994	107.252731323242
1995	107.08447265625
1996	106.81111907959
1997	106.646636962891
1998	106.859008789062
1999	107.023086547852
2000	107.383682250977
2001	106.740676879883
2002	106.958320617676
2003	108.030838012695
2004	108.201370239258
2005	107.940986633301
2006	107.839912414551
2007	107.652893066406
2008	107.348289489746
2009	107.019401550293
2010	106.750358581543
2011	107.072776794434
2012	107.048240661621
2015	106.059417724609
2016	105.680366516113
2017	105.039421081543
2018	104.561111450195
2019	104.578910827637
2020	104.338813781738
2021	104.378402709961