Year	gross (GPI)
1971	0.54601001739502
1972	0.542999982833862
1978	0.888880014419556
1981	1.07923996448517
1983	1.00094997882843
1984	0.946229994297028
1985	0.889980018138885
1986	0.900390028953552
1987	0.973529994487762
1988	1.04126000404358
1989	1.06681001186371
1990	1.09407997131348
1991	1.08619999885559
1992	1.09224998950958
1993	1.02751994132996
1994	1.10675001144409
1995	1.06843996047974
1996	1.09086000919342
1997	1.17465996742249
1998	1.16990995407104
1999	1.26415002346039
2000	1.26479995250702
2001	1.31436002254486
2002	1.34159004688263
2003	1.36431002616882
2004	1.36783003807068
2005	1.33887994289398
2006	1.29716002941132
2007	1.30860996246338
2008	1.26893997192383
2009	1.28373003005981
2010	1.25866997241974
2011	1.2440299987793
2012	1.23923003673553
2013	1.23276996612549
2014	1.24158000946045
2015	1.24035000801086
2016	1.27751004695892
2017	1.30886995792389
2018	1.3303200006485
2019	1.32822000980377
2020	1.33726000785828
2021	1.35378003120422
2022	1.32611000537872