Year	gross (GPI)
1983	0.478060007095337
1984	0.489490002393723
1986	0.470809996128082
1992	0.414869993925095
2010	0.660660028457642
2011	0.629809975624084
2012	0.641719996929169
2013	0.714380025863647
2015	0.793060004711151
2016	0.771276593208313
2017	0.870556175708771
2018	0.921816349029541
2019	0.960901498794556
2020	0.961902856826782