Bi-annual US dollars 1987-06-30 113 1987-12-31 119 1988-06-30 97 1988-12-31 20 1989-06-30 19 1989-12-31 8 1990-06-30 99 1990-12-31 98 1991-06-30 86 1991-12-31 103 1992-06-30 99 1992-12-31 86 1993-06-30 90 1993-12-31 84 1994-06-30 100 1994-12-31 6 1995-06-30 19 1995-12-31 59 1996-06-30 51 1996-12-31 10 1997-06-30 10 1997-12-31 25 1998-06-30 20 1998-12-31 45 1999-06-30 66