Year	gross (GPI)
1971	0.435790002346039
1972	0.441540002822876
1973	0.449710011482239
1974	0.463499993085861
1975	0.490790009498596
1976	0.492799997329712
1977	0.473010003566742
1978	0.476040005683899
1979	0.479449987411499
1980	0.496969997882843
1981	0.524820029735565
1982	0.54355001449585
1983	0.565159976482391
1984	0.600870013237
1985	0.61353999376297
1986	0.626309990882874
1987	0.635460019111633
1989	0.63375997543335
1992	0.689869999885559
1993	0.712830007076263
1994	0.732659995555878
1995	0.751020014286041
1996	0.783770024776459
1997	0.806360006332397
1998	0.832220017910004
1999	0.856649994850159
2000	0.880789995193481
2001	0.912199974060059
2002	0.91143000125885
2003	0.980799973011017
2004	1.0106600522995
2005	1.03284001350403
2006	1.04951000213623
2007	1.04936003684998
2008	1.06246995925903
2009	1.04315996170044
2010	1.02645003795624
2011	1.03847002983093
2012	1.04500997066498
2013	1.04388999938965
2014	1.05557000637054
2015	1.06764996051788
2016	1.07556998729706
2017	1.08311998844147
2018	1.09420001506805
2019	1.10830998420715
2020	1.11924004554749
2021	1.13089001178741
2022	1.12258577346802