Year	gross (GPI)
1979	0.6042799949646
2005	0.964429974555969
2009	0.931209981441498
2015	1.00355005264282
2016	0.956160008907318
2017	0.957579970359802
2018	0.977729976177216
2019	0.960340023040771
2020	0.974160015583038
2021	0.988870024681091