Year	gross (GPI)
2001	0.845820009708405
2002	0.844110012054443
2003	0.858240008354187
2004	0.855419993400574
2005	0.876820027828217
2006	0.86489999294281
2007	0.840409994125366
2008	0.868369996547699
2009	0.890100002288818
2010	0.896589994430542
2011	0.884599983692169
2012	0.88918000459671
2013	0.896939992904663
2014	0.922789990901947
2015	0.913160026073456
2016	0.93247002363205
2017	0.940039992332459
2018	0.93164998292923