Bi-annual US dollars 1987-06-30 114 1987-12-31 136 1988-06-30 164 1988-12-31 58 1989-06-30 105 1989-12-31 50 1990-06-30 110 1990-12-31 127 1991-06-30 50 1991-12-31 92 1992-06-30 70 1992-12-31 21 1993-06-30 20 1993-12-31 28 1994-06-30 42 1994-12-31 75 1995-06-30 10 1995-12-31 102 1996-06-30 104 1996-12-31 80 1997-06-30 48 1997-12-31 10 1998-06-30 122 1998-12-31 0 1999-06-30 39