Year	% gross
1970	9.5646800994873
1971	9.47840023040771
1972	9.44293975830078
1973	9.36693954467773
1974	9.39385986328125
1975	10.5210103988647
1976	12.2319297790527
1977	13.0727396011353
1978	13.4466199874878
1979	14.1950197219849
1980	14.3496398925781
1981	14.426549911499
1982	14.3850898742676
1983	14.2545795440674
1984	14.6229600906372
1985	14.0073099136353
1986	13.8136196136475
1987	13.983510017395
1988	13.948390007019
1989	14.5004100799561
1990	14.5450601577759
1991	14.8752403259277
1992	15.1556901931763
1993	14.4640197753906
1994	14.3689603805542
1995	14.6095504760742
1996	15.1166296005249
1997	15.6649799346924
1998	16.7004299163818
1999	15.9245595932007
2000	16.6115207672119
2001	16.7032203674316
2002	17.2670993804932
2003	17.6619396209717
2004	18.39621925354
2005	19.6408500671387
2006	22.1571598052979
2007	21.940860748291
2008	23.5220508575439
2009	25.1525707244873
2010	26.5779399871826
2011	25.297700881958
2012	25.1630592346191
2013	24.8920497894287
2014	27.7101097106934
2015	28.5054092407227
2016	28.2893695831299
2017	29.1737899780273
2018	29.4942302703857
2019	30.6725597381592
2020	31.0406608581543