Year	gross (GPI)
1972	0.633149981498718
1973	0.645259976387024
1974	0.673940002918243
1975	0.683780014514923
1976	0.70169997215271
1977	0.723299980163574
1978	0.738009989261627
1979	0.743640005588531
1980	0.751869976520538
1981	0.771759986877441
1982	0.787540018558502
1983	0.803390026092529
1984	0.81046998500824
1985	0.809989988803864
1986	0.831160008907318
1987	0.847270011901855
1988	0.85861998796463
1989	0.857039988040924
1990	0.857620000839233
1991	0.863059997558594
1992	0.864910006523132
1993	0.934700012207031
1994	0.951240003108978
1995	0.901080012321472
1996	0.902480006217957
1999	0.940259993076324
2000	0.946860015392303
2001	0.949329972267151
2002	0.950739979743958
2004	1.00817000865936
2005	1.00834000110626
2006	1.01961004734039
2007	1.01943004131317
2008	1.01150000095367
2009	1.0131299495697
2010	1.0208899974823
2011	1.02409994602203
2012	1.02166998386383
2013	1.01822996139526
2014	1.01877999305725
2015	1.02040994167328
2016	1.02665996551514
2017	1.0315899848938
2018	1.00899004936218
2019	1.02989995479584