Bi-annual	US dollars
1987-06-30	2240
1987-12-31	2278
1988-06-30	2077
1988-12-31	2068
1989-06-30	1916
1989-12-31	1888
1990-06-30	1625
1990-12-31	1731
1991-06-30	1660
1991-12-31	1909
1992-06-30	1749
1992-12-31	1804
1993-06-30	1919
1993-12-31	1472
1994-06-30	1364
1994-12-31	1455
1995-06-30	1642
1995-12-31	1857
1996-06-30	1835
1996-12-31	1698
1997-06-30	1304
1997-12-31	1668
1998-06-30	2134
1998-12-31	1772
1999-06-30	1777