Year	gross (GPI)
1970	0.723959982395172
1971	0.8473299741745
1972	0.858650028705597
1973	0.847280025482178
1974	0.871540009975433
1975	0.884400010108948
1976	0.885370016098022
1977	0.908819973468781
1978	0.807009994983673
1979	0.818970024585724
1980	0.830470025539398
1981	0.858669996261597
1982	0.860920011997223
1983	0.883819997310638
1993	0.886290013790131
1996	0.888639986515045
1998	0.892889976501465
1999	0.840929985046387
2000	0.889880001544952
2001	0.899479985237122
2002	0.896499991416931
2004	0.912050008773804
2005	0.920920014381409
2006	0.931800007820129
2007	0.94021999835968
2008	0.952820003032684
2009	0.953949987888336
2010	0.941240012645721
2011	0.933849990367889
2012	0.938570022583008
2013	0.937889993190765
2014	0.947809994220734
2015	0.942170023918152
2016	0.946730017662048
2017	0.950789988040924
2018	0.953310012817383
2019	0.961179971694946
2020	0.979820013046265
2021	1.0171799659729