Year	gross (GPI)
1971	1.27941000461578
1972	1.33858001232147
1973	1.47791004180908
1974	1.3430700302124
1975	1.33158004283905
1976	1.40960001945496
1977	1.4041999578476
1978	1.10065996646881
1979	0.895070016384125
1980	1.0535900592804
1981	0.989589989185333
1982	1.1569299697876
1985	1.40625
1986	1.482990026474
1987	1.35004997253418
1988	1.44955003261566
1991	1.34271001815796
1992	1.42056000232697
1993	1.41275000572205
1994	1.45572996139526
1995	1.49566996097565
1996	1.53459000587463
1999	1.52191996574402
2003	1.4951399564743
2005	1.67762005329132
2006	1.6949599981308
2011	1.41165995597839
2012	1.50027000904083
2013	1.54660999774933
2014	1.481330037117
2015	1.47256994247437
2016	1.48371994495392
2017	1.50012004375458
2018	1.49379003047943
2019	1.47005999088287
2020	1.45571994781494
2021	1.37847995758057
2022	1.32669997215271