Year	% gross
1971	22.9450206756592
1972	24.7733402252197
1973	27.1505508422852
1974	29.8929195404053
1975	33.0618896484375
1976	36.5298309326172
1977	39.3071517944336
1978	41.3908195495605
1979	45.4929504394531
1980	47.160099029541
1981	50.5994987487793
1982	52.9599494934082
1983	55.8262596130371
1984	53.0994491577148
1985	56.4329299926758
1986	56.9398002624512
1987	57.3968505859375
1988	58.1155014038086
1993	55.7268218994141
1996	53.2277488708496
1998	55.3980102539062
1999	56.5092010498047
2000	56.3055000305176
2001	56.8470802307129
2002	57.5722618103027
2003	57.6054000854492
2004	57.9729385375977
2005	60.9712982177734
2006	63.4785308837891
2007	65.0637283325195
2009	89.8251495361328
2010	93.6502990722656
2011	98.3720321655273
2012	102.11311340332
2013	104.746276855469
2014	107.651092529297
2015	106.690208435059
2016	105.870399475098
2017	104.034286499023
2018	103.139450073242
2019	101.592910766602
2020	101.083847045898
2021	100.65258026123
2022	99.2673492431641