Year	gross (GPI)
1971	0.0566399991512299
1972	0.0683100000023842
1974	0.102860003709793
2007	0.348100006580353
2008	0.352710008621216
2009	0.308140009641647
2011	0.443250000476837
2012	0.547519981861115
2013	0.451629996299744
2016	0.555149972438812
2020	0.593029975891113