Year	% gross
1971	107.335731506348
1972	109.152389526367
1973	110.400047302246
1974	111.020393371582
1975	106.572998046875
1976	106.930038452148
1977	107.631973266602
1978	103.65161895752
1979	98.3220062255859
1980	94.2949523925781
1981	94.2022171020508
1982	95.4694366455078
1983	98.3568801879883
1984	102.669708251953
1985	104.348083496094
1986	104.954063415527
1987	104.549560546875
1988	103.341743469238
1989	100.382911682129
1990	97.9606475830078
1991	99.6355819702148
1992	103.644523620605
1993	106.961990356445
1994	107.6220703125
1995	108.893432617188
1996	112.742080688477
1997	115.111869812012
2012	103.412643432617
2013	110.313636779785
2014	110.709022521973
2015	101.129829406738
2016	114.899360656738
2017	82.615119934082
2018	93.04443359375
2019	97.1977920532227
2020	95.3105926513672
