Bi-annual US dollars 1987-06-30 56 1987-12-31 68 1988-06-30 67 1988-12-31 34 1989-06-30 40 1989-12-31 42 1990-06-30 35 1990-12-31 41 1991-06-30 13 1991-12-31 11 1992-06-30 4 1992-12-31 21 1993-06-30 36 1993-12-31 81 1994-06-30 99 1994-12-31 95 1995-06-30 118 1995-12-31 109 1996-06-30 129 1996-12-31 110 1997-06-30 100 1997-12-31 114 1998-06-30 80 1998-12-31 68 1999-06-30 106