Year	gross (GPI)
1971	0.401730000972748
1981	0.459820002317429
1982	0.453240007162094
1983	0.442019999027252
1984	0.442129999399185
1985	0.425960004329681
1986	0.429199993610382
1987	0.412099987268448
1989	0.41525000333786
1990	0.419270008802414
1991	0.429080009460449
1993	0.432850003242493
1994	0.449319988489151
1996	0.485469996929169
1999	0.555509984493256
2001	0.618799984455109
2002	0.641359984874725
2003	0.670920014381409
2004	0.682900011539459
2005	0.707319974899292
2006	0.727469980716705
2008	0.752470016479492
2011	0.779540002346039
2012	0.774029850959778
2013	0.774895191192627
2014	0.785929977893829
2015	0.765342056751251
2016	0.768221795558929
2018	0.797581851482391
2019	0.804893851280212