Year	gross (GPI)
1972	0.608280003070831
1973	0.661469995975494
1977	0.969290018081665
1979	1.03810000419617
1992	1.22405004501343
1993	1.28945004940033
1995	1.39547002315521
1998	1.38838005065918
2007	1.30001997947693
2011	1.28925001621246
2012	1.22093999385834
2018	1.32123994827271