Year	% gross
1971	39.4409484863281
1972	37.125129699707
1973	36.106689453125
1974	35.7762794494629
1975	36.1082992553711
1976	36.9146995544434
1977	37.3857383728027
1978	35.9600296020508
1979	35.5190505981445
1980	33.9725494384766
1981	36.9612808227539
1982	40.1645317077637
1983	43.2975807189941
1984	43.5326118469238
1985	48.0531311035156
1986	48.8205108642578
1987	48.1581687927246
1988	47.9328308105469
1989	47.1057205200195
1990	47.103588104248
1991	34.673038482666
1992	39.1249504089355
1993	54.0277214050293
1994	61.5245590209961
1995	72.959846496582
1996	76.1167297363281
1997	76.4934616088867
1998	79.3157196044922
1999	75.9463195800781
2000	72.9763870239258
2001	71.1669235229492
2002	72.0822677612305
2003	71.9687881469727
2004	72.7779312133789
2005	75.51904296875
2006	80.1039123535156
2007	84.0453872680664
2008	85.0835723876953
2010	84.2652435302734
2011	82.5462417602539
2012	82.0709381103516
2013	77.6723403930664
2014	71.8322219848633
2015	68.6873779296875
2016	67.4406509399414
2017	64.4906768798828
2018	60.8844413757324
2019	58.3979911804199
2020	58.5376281738281