Year	US Dollars
1960	574.58056
1961	670.38486
1962	866.83965
1963	1779.10263
1964	1120.32355
1965	1780.23258
1966	1709.36938
1967	1886.19397
1968	2864.94251
1969	4633.23961
1970	4751.05971
1971	4722.04968
1972	4494.10833
1973	4655.17246
1974	5050.65406
1975	5326.47861
1976	5743.50751
1977	5761.27291
1978	6249.84557
1979	6770.34062
1980	6196.55932
1981	6848.05513
1982	7146.20022
1983	5230.13209
1984	6446.14567
1985	4961.7676
1986	6544.45973
1987	4760.16748
1988	3591.46803
1989	3461.69781
1990	1302.8624
1991	580.92831
1992	153.54887
1993	1855.13467
1994	48.13729
1995	-14.3687
1996	-29.41893
1997	11.34551
1998	2.91967
1999	1.57404