Year	gross (GPI)
1971	0.165619999170303
1972	0.173960000276566
1973	0.179759994149208
1974	0.193250000476837
1976	0.209140002727509
1977	0.217209994792938
1979	0.205229997634888
1980	0.203069999814034
1987	0.204180002212524
1994	0.293769985437393
1995	0.314359992742538
1997	0.346980005502701
1999	0.340240001678467
2007	0.506429970264435
2008	0.552089989185333
2009	0.528699994087219
2010	0.51282000541687
2011	0.666620016098022
2013	0.611620008945465
2014	0.574500024318695
2015	0.651319980621338
2016	0.688539981842041
2017	0.701770007610321
2019	0.764500021934509
2020	0.805649995803833