Year	% gross
1971	111.175048828125
1972	115.415962219238
1973	110.029167175293
1974	111.37776184082
1975	112.16040802002
1976	111.844871520996
1977	111.052047729492
1978	110.624839782715
1979	110.497108459473
1980	110.034118652344
1981	109.475143432617
1982	109.810966491699
1983	109.743171691895
1984	109.684638977051
1985	109.653793334961
1986	109.299301147461
1987	110.22216796875
1988	109.257080078125
1989	109.526321411133
1990	109.46312713623
1991	109.327140808105
1992	107.910331726074
1993	109.244438171387
1994	108.881248474121
1995	107.80290222168
1996	107.210586547852
1997	106.181091308594
1998	105.36393737793
1999	104.299728393555
2000	104.224510192871
2001	104.563087463379
2002	105.450859069824
2003	105.158348083496
2004	105.000923156738
2005	104.357879638672
2006	103.610877990723
2007	103.025680541992
2008	102.449981689453
2009	102.095718383789
2010	101.211227416992
2011	100.813041687012
2012	100.473442077637
2013	103.107582092285
2014	102.538467407227
2015	102.144233703613
2016	102.130096435547
2017	102.50511932373
2018	102.638717651367
2019	103.185317993164
2020	103.410423278809
2021	102.899139404297