Year	gross (GPI)
1970	1.3193199634552
1971	1.32397997379303
1972	1.22817003726959
1973	1.28556001186371
1974	1.21707999706268
1975	1.36117994785309
1976	1.31765997409821
1978	1.2350800037384
1979	1.19886994361877
1980	1.17682003974915
1981	1.16491997241974
1982	1.17736005783081
1983	1.09591996669769
1985	1.01952004432678
1986	0.984210014343262
1987	0.943069994449615
1988	0.953130006790161
1989	0.975040018558502
1991	0.992110013961792
1992	1.01170003414154
1993	1.02909004688263
1994	1.03308999538422
1995	1.00039994716644
1996	1.01602005958557
1998	0.998359978199005
1999	1.0764000415802
2000	1.09803998470306
2001	1.07937002182007
2002	1.07814002037048
2003	1.08087003231049
2004	1.10548996925354
2005	1.07246994972229
2006	1.07225000858307
2007	1.09820997714996
2008	1.12363004684448
2009	1.10715997219086
2010	1.06274998188019
2011	1.05307996273041
2012	0.997940003871918
2013	1.09528994560242
2014	1.05227994918823
2015	1.07266998291016
2016	1.1086699962616
2017	1.11833000183105
2018	1.06833004951477
2019	1.06480002403259
2020	1.08508002758026
2021	1.08906996250153