Year	gross (GPI)
1971	0.668720006942749
1998	0.789420008659363
1999	0.810949981212616
2000	0.818300008773804
2001	0.835860013961792
2002	0.848770022392273
2003	0.860019981861115
2004	0.876280009746552
2006	0.899569988250732
2007	0.903710007667542
2008	0.91483998298645
2020	1.00029003620148
2021	1.03767263889313
