Year	gross (GPI)
1970	0.886789977550507
1980	1.01888000965118
1982	1.13352000713348
1983	1.08175003528595
1984	1.16517996788025
1991	1.22572004795074
2006	1.2453099489212
2007	1.25938999652863
2008	1.27608001232147
2010	1.23055994510651
2011	1.22063994407654
2012	1.21714997291565