Year	% gross
1970	7.661789894104
1971	7.80606985092163
1972	7.94863986968994
1973	8.09899044036865
1974	8.37289047241211
1975	9.04679012298584
1976	9.63523960113525
1977	10.2489595413208
1978	10.663610458374
1979	11.2141704559326
1980	11.784740447998
1981	12.5019998550415
1982	13.3285903930664
1983	13.9910202026367
1984	14.5872602462769
1985	15.0614995956421
1986	15.8501100540161
1987	16.3778400421143
1988	17.0290508270264
1989	16.9463691711426
1990	16.7822608947754
1991	17.2578296661377
1992	17.2249908447266
1993	17.190990447998
1994	17.5940494537354
1995	17.92919921875
1996	18.1459903717041
1997	14.9747400283813
1998	17.083740234375
1999	18.175220489502
2000	19.9855499267578
2001	21.2887592315674
2002	22.0165596008301
2003	23.4932708740234
2004	25.4730091094971
2005	28.0441799163818
2006	31.5358200073242
2007	34.235408782959
2008	36.6632804870605
2009	38.6593208312988
2010	40.5991897583008
2011	43.0281982421875
2012	45.5616111755371
2013	47.1373596191406
2014	48.9321517944336
2015	51.1239013671875
2016	52.6582298278809
2017	54.8464813232422
2018	55.6225700378418
2019	56.9350891113281
2020	56.225959777832