Year	gross (GPI)
1971	0.610319972038269
1972	0.741129994392395
1973	0.7951899766922
1974	0.81292998790741
1976	0.834999978542328
1977	0.924549996852875
1978	0.90745997428894
1979	0.917259991168976
1980	0.981459975242615
1981	1.00037002563477
1982	1.02945005893707
1983	1.00434005260468
1984	1.0211900472641
1985	1.02698004245758
1986	1.0267299413681
1987	1.04536998271942
1988	1.06922996044159
1989	1.08674001693726
1990	1.10514998435974
1991	1.12529003620148
1992	1.14032995700836
1993	1.07386004924774
1994	1.08361005783081
1995	1.1041100025177
1996	1.17604994773865
1998	1.22343003749847
1999	1.24876999855042
2000	1.26715004444122
2001	1.24696004390717
2002	1.27663004398346
2003	1.28944003582001
2004	1.29056000709534
2005	1.28102004528046
2006	1.28366005420685
2007	1.29089999198914
2008	1.30610001087189
2009	1.31394004821777
2010	1.30919003486633
2011	1.2948499917984
2012	1.28652000427246
2013	1.27278995513916
2014	1.28464996814728
2015	1.28112995624542
2016	1.26285004615784
2017	1.26423001289368
2018	1.26526999473572
2019	1.27155995368958
2020	1.27427005767822
2021	1.27216994762421
2022	1.28394997119904