Year	% gross
1971	99.2846221923828
1972	99.6804962158203
1973	100.943176269531
1974	103.981422424316
1975	106.101737976074
1976	108.028259277344
1977	106.73307800293
1978	103.021949768066
1979	100.998199462891
1980	101.034660339355
1981	102.436508178711
1982	104.593696594238
1983	107.029159545898
1984	109.724632263184
1985	111.470291137695
1986	111.323181152344
1987	107.587928771973
1988	104.414260864258
1989	102.329627990723
1990	103.070182800293
1991	104.34058380127
1992	110.946189880371
1993	114.16455078125
1994	117.158798217773
1995	118.796180725098
1996	117.344917297363
1999	109.346488952637
2000	110.256050109863
2001	110.978538513184
2002	112.714950561523
2003	115.448760986328
2004	116.262092590332
2005	119.814277648926
2006	119.317596435547
2007	118.454719543457
2008	118.345283508301
2009	118.546043395996
2010	119.691818237305
2011	120.773536682129
2012	120.386581420898
2013	119.202346801758
2014	118.719512939453
2015	117.408920288086
2016	116.285110473633
2017	115.261276245117
2018	113.855857849121
2019	113.164390563965
2020	111.711196899414