Year	US Dollars adjusted for inflation)
1970	999.3
1971	1017
1972	1035
1973	1002
1974	999.2
1975	979.1
1976	919.8
1977	901.6
1978	829.3
1979	877.8
1980	892.1
1981	969
1982	1005
1983	990.8
1984	1013
1985	1126
1986	1144
1987	1084
1988	1122
1989	1290
1990	1309
1991	1315
1992	1348
1993	1325
1994	1360
1995	1372
1996	1410
1997	1433
1998	1221
1999	1277
2000	1257
2001	1264
2002	1424
2003	1412