Year	% gross
1970	2.043869972229
1971	2.079509973526
1972	2.17583990097046
1973	2.19144010543823
1974	2.26736998558044
1975	2.28034996986389
1976	2.27487993240356
1977	2.47239995002747
1978	2.54639005661011
1979	2.89816999435425
1980	3.00046992301941
1981	3.12674999237061
1982	3.28655004501343
1983	3.4711799621582
1984	3.58082008361816
1985	3.61685991287231
1986	3.63926005363464
1987	3.64803004264832
1988	3.51873993873596
1989	3.49188995361328
1990	3.57420992851257
1991	3.60916996002197
1992	3.58418989181519
1993	3.69197010993958
1994	3.66392993927002
1995	3.70068001747131
1996	3.83173990249634
1997	3.95363998413086
1998	4.13452005386353
1999	4.365149974823
2000	4.67097997665405
2001	5.16405010223389
2002	5.30767011642456
2003	5.44438982009888
2004	5.61290979385376
2005	6.04313993453979
2006	6.52782011032104
2007	6.97329998016357
2008	7.63298988342285
2009	8.41831016540527
2010	9.18148994445801
2011	9.55039024353027
2012	9.93142986297607
2013	10.2918796539307
2014	10.5837097167969
2015	10.91273021698
2016	11.0434198379517
2017	11.1810703277588
2018	11.6321201324463
2019	12.2130002975464
2020	12.3456602096558
2021	12.3402795791626
2022	12.54421043396