Year	% gross
1970	6.43533992767334
1971	5.10918998718262
1972	5.10265016555786
1973	5.01380014419556
1974	4.97432994842529
1975	6.03993988037109
1976	6.00675010681152
1977	6.05620002746582
1978	4.98656988143921
1979	4.92507982254028
1980	4.91556978225708
1981	4.99081993103027
1982	5.08895015716553
1983	5.18452978134155
1984	5.3096399307251
1985	5.35831022262573
1986	5.36082983016968
1987	5.31263017654419
1988	5.51070976257324
1989	5.67199993133545
1990	5.97764015197754
1991	6.03249979019165
1992	6.3012900352478
1993	6.60620021820068
1994	6.85777997970581
1995	7.10059022903442
1996	7.99241018295288
1997	8.14702987670898
1998	8.69629955291748
1999	8.65503025054932
2000	9.26723003387451
2001	10.091609954834
2002	10.242639541626
2003	11.0644903182983
2004	11.5784101486206
2005	11.9235000610352
2006	12.1314897537231
2007	12.9445199966431
2008	14.1955795288086
2009	15.9180097579956
2010	16.3329601287842
2011	17.2792091369629
2012	17.9791297912598
2013	18.5469493865967
2014	18.8605804443359
2015	19.035680770874
2016	18.8894691467285
2017	19.4174098968506
2018	19.6200103759766
2019	20.4112606048584
2020	20.8437309265137
2021	21.4240608215332