Year	gross (GPI)
1981	0.257180005311966
1982	0.272060006856918
1983	0.293150007724762
1984	0.313699990510941
1985	0.310369998216629
1986	0.336030006408691
1987	0.353789985179901
1988	0.382409989833832
1989	0.400950014591217
1990	0.42577001452446
1991	0.451070010662079
1992	0.491320013999939
1993	0.520120024681091
1994	0.555469989776611
1995	0.592410027980804
1996	0.6285799741745
1999	0.667770028114319
2000	0.676140010356903
2001	0.679799973964691
2002	0.693499982357025
2003	0.721819996833801
2005	0.812160015106201
2006	0.841750025749207
2007	0.872780025005341
2008	0.901679992675781
2009	0.891680002212524
2010	0.976180016994476
2011	0.995389997959137
2012	1.02473998069763
2013	1.0307400226593
2014	1.03701996803284
2015	1.04752004146576
2016	1.05752003192902
2017	1.07629942893982
2019	1.07304000854492
2020	1.03255999088287
2021	1.0245475769043
2022	0.987173140048981