Bi-annual US dollars 1987-06-30 8 1987-12-31 8 1988-06-30 7 1988-12-31 11 1989-06-30 8 1989-12-31 6 1990-06-30 7 1990-12-31 8 1991-06-30 10 1991-12-31 7 1992-06-30 11 1992-12-31 8 1993-06-30 75 1993-12-31 10 1994-06-30 17 1994-12-31 28 1995-06-30 10 1995-12-31 16 1996-06-30 5 1996-12-31 58 1997-06-30 -12 1997-12-31 87 1998-06-30 0 1998-12-31 5 1999-06-30 0