Year	gross (GPI)
1993	1.04516005516052
1997	1.13357996940613
1998	1.06639003753662
1999	1.01188004016876
2000	1.05353999137878
2006	0.995419979095459
2010	1.00540995597839
2011	1.00685000419617
2012	1.0095100402832
2013	1.01926004886627
2014	1.02521002292633
2015	1.03478002548218
2016	1.0263500213623
2017	1.00917994976044
2018	1.00812995433807
2019	1.00978004932404
2020	1.00129997730255