Bi-annual US dollars 1987-06-30 71 1987-12-31 77 1988-06-30 280 1988-12-31 141 1989-06-30 116 1989-12-31 100 1990-06-30 87 1990-12-31 44 1991-06-30 75 1991-12-31 73 1992-06-30 86 1992-12-31 76 1993-06-30 59 1993-12-31 71 1994-06-30 31 1994-12-31 66 1995-06-30 60 1995-12-31 90 1996-06-30 48 1996-12-31 106 1997-06-30 101 1997-12-31 104 1998-06-30 170 1998-12-31 47 1999-06-30 63