Year US Dollars adjusted for inflation) 1960 838.2 1961 922.9 1962 901.6 1963 921.4 1964 958.1 1965 1027 1966 1168 1967 1237 1968 1293 1969 1352 1970 1302 1971 1376 1972 1403 1973 1287 1974 1316 1975 1282 1976 1321 1977 1291 1978 1310 1979 1351 1980 1314 1981 1104 1982 1067 1983 977.4 1984 1029 1985 932.6 1986 869.7 1987 869.7 1988 902.2 1989 920.1 1990 906.7 1991 890.6 1992 826 1993 815 1994 883.9 1995 898.4 1996 878.7 1997 874.2 1998 909.8 1999 868.8 2000 823.2 2001 784 2002 731.4 2003 788.5 2004 773.7