Year	gross (GPI)
1971	0.240380004048347
1972	0.293430000543594
1973	0.336939990520477
1976	0.534250020980835
1979	0.796750009059906
1980	0.707239985466003
1981	0.75533002614975
1982	0.794319987297058
1983	0.6876500248909
1984	0.903970003128052
1985	0.940590023994446
1986	0.897270023822784
1988	0.761020004749298
1990	0.721430003643036
1994	0.809759974479675
1995	0.899580001831055
1996	0.875140011310577
1997	0.997600018978119
2004	1.47070002555847
2005	1.52215003967285
2006	1.54488003253937
2007	1.53136003017426
2008	1.29329001903534
2009	1.51049995422363
2010	1.58477997779846
2011	1.55672001838684
2012	1.50004005432129