Year	gross (GPI)
1979	0.652490019798279
1980	0.649169981479645
1982	0.770060002803802
1983	0.840139985084534
1984	0.780170023441315
1985	0.831740021705627
1988	0.722590029239655
1989	0.752810001373291
1998	1.08142995834351
1999	1.03859996795654
2000	1.07711005210876
2001	1.20090997219086
2002	1.23436999320984
2003	1.3049099445343
2004	1.25554001331329
2005	1.27587997913361
2006	1.23984003067017
2007	1.26679003238678
2008	1.26361000537872
2009	1.25325000286102
2010	1.27700996398926
2011	1.25047028064728
2012	1.25599110126495
2013	1.26499438285828
2014	1.25431084632874
2015	1.22871589660645
2016	1.14589893817902
2017	1.13618457317352
2018	1.18069243431091
2019	1.2226095199585
2020	1.23221623897552
2021	1.23942482471466
2022	1.24581944942474