Year	gross (GPI)
1993	1.05492997169495
1997	1.07936000823975
1998	1.04428005218506
1999	1.00592005252838
2000	1.03445994853973
2006	0.996510028839111
2010	1.00502002239227
2011	1.00604999065399
2012	1.00756001472473
2013	1.01269996166229
2014	1.0152599811554
2015	1.02092003822327
2016	1.01620995998383
2017	1.01248002052307
2018	1.01218998432159
2019	1.01346004009247
2020	0.999840021133423