Year US Dollars 1974 128.0683 1975 115.29258 1976 145.26839 1977 98.57105 1978 205.76654 1979 45.18256 1980 87.1345 1981 55.29491 1982 30.43409 1983 19.41549 1984 17.12915 1985 3.28438 1986 88.75873 1987 94.90791 1988 504.67524 1989 49.42141 1990 114.8807 1991 -10.60717 1992 0 1993 -15.31394 1994 -32.46547 1995 -17.37699 1996 -59.36714