Bi-annual US dollars 1987-06-30 624 1987-12-31 957 1988-06-30 752 1988-12-31 886 1989-06-30 834 1989-12-31 716 1990-06-30 813 1990-12-31 1048 1991-06-30 1312 1991-12-31 1072 1992-06-30 1098 1992-12-31 898 1993-06-30 1167 1993-12-31 1273 1994-06-30 1468 1994-12-31 1166 1995-06-30 983 1995-12-31 746 1996-06-30 632 1996-12-31 1904 1997-06-30 2204 1997-12-31 1450 1998-06-30 1707 1998-12-31 1641 1999-06-30 2185