Year	gross (GPI)
1971	0.288819998502731
1972	0.316859990358353
1973	0.316020011901855
1974	0.32914999127388
1975	0.349339991807938
1976	0.327450007200241
1977	0.366540014743805
1978	0.388209998607635
1979	0.37415999174118
1980	0.388639986515045
1986	0.372159987688065
1987	0.367379993200302
1988	0.386359989643097
1990	0.404159992933273
1992	0.267820000648499
2003	0.80119001865387
2004	0.787039995193481
2005	0.869350016117096
2006	0.849569976329803
2007	0.851890027523041
2008	0.854240000247955
2009	0.855719983577728
2011	0.935714304447174
2012	0.96927535533905
2013	0.99238520860672
2014	1.07100462913513
2015	0.88381016254425
2016	0.870343744754791
2017	0.858049511909485
2018	0.852593183517456
2019	0.957542300224304
2020	0.963559985160828
2021	0.940578043460846
2022	0.927630007266998
2023	0.92577999830246