Year	gross (GPI)
1970	0.826290011405945
1971	0.86710000038147
1972	0.857829988002777
1973	0.867820024490356
1974	0.872889995574951
1975	0.868089973926544
1976	0.903649985790253
1977	0.923389971256256
1978	0.905110001564026
1979	0.918299973011017
1980	0.93708997964859
1981	0.930069983005524
1982	0.915579974651337
1983	0.927569985389709
1984	0.93928998708725
1985	0.965290009975433
1986	0.986930012702942
1987	0.994719982147217
1988	1.01972997188568
1989	1.03709995746613
1990	1.04172003269196
1991	1.03943002223969
1992	1.07414996623993
1993	1.06130003929138
1994	1.08071994781494
1995	1.11758005619049
1996	1.12255001068115
1997	1.11752998828888
1998	1.16341996192932
1999	1.1628600358963
2000	1.17289996147156
2001	1.2070300579071
2002	1.22641003131866
2003	1.20455002784729
2004	1.20278000831604
2005	1.21712005138397
2006	1.20538997650146
2007	1.22184002399445
2008	1.22722005844116
2009	1.22108995914459
2010	1.22250998020172
2011	1.21701002120972
2012	1.25483000278473
2013	1.26187002658844
2014	1.27259004116058
2015	1.30067002773285
2016	1.31080996990204
2017	1.33379995822906
2018	1.333899974823
2019	1.32664000988007
2020	1.32831001281738
2021	1.31394994258881