Year	gross (GPI)
1970	0.708559989929199
1971	0.779250025749207
1973	0.81275999546051
1974	0.829180002212524
1975	0.843580007553101
1976	0.854080021381378
1977	0.868550002574921
1978	0.883459985256195
1979	0.885450005531311
1980	0.917119979858398
1981	0.888390004634857
1983	0.912840008735657
1984	0.937200009822845
1986	0.931919991970062
1987	0.927950024604797
1989	0.93681001663208
1990	0.942399978637695
1991	0.946399986743927
1992	0.950500011444092
1993	0.965300023555756
1994	0.969169974327087
1995	0.970560014247894
1996	0.972400009632111
1997	0.974179983139038
1998	0.980180025100708
1999	0.985459983348846
2000	0.985809981822968
2001	0.988200008869171
2002	0.990249991416931
2003	0.99711000919342
2004	1.00010001659393
2005	1.00123000144958
2006	1.00108003616333
2007	0.99974000453949
2008	0.995270013809204
2009	0.989780008792877
2010	0.994329988956451
2011	0.992229998111725
2012	0.986450016498566
2013	0.97869998216629
2014	0.976909995079041
2015	0.979680001735687
2016	0.983780026435852
2017	0.986959993839264
2018	0.990040004253387
2019	0.994270026683807
2020	0.998340010643005