Year	gross (GPI)
1971	0.319609999656677
1972	0.346080005168915
1980	0.587589979171753
1981	0.585169970989227
1982	0.619870007038116
1983	0.610210001468658
1985	0.651229977607727
1992	0.947650015354156
1996	1.014240026474
1999	1.05633997917175
2000	1.10852003097534
2001	1.11417996883392
2002	1.15023994445801
2003	1.1863499879837
2004	1.12679994106293
2005	1.14445996284485
2006	1.15775001049042
2007	1.18449997901917
2008	1.20614004135132
2009	1.17343997955322
2010	1.17326998710632
2011	1.14560997486115
2012	1.1933000087738
2013	1.19447004795074
2014	1.23737001419067
2015	1.08441996574402
2016	1.25204002857208
2017	1.24793994426727
2018	1.25450003147125
2019	1.23959994316101