Bi-annual US dollars 1987-06-30 2 1987-12-31 0 1988-06-30 0 1988-12-31 0 1989-06-30 29 1989-12-31 32 1990-06-30 14 1990-12-31 21 1991-06-30 65 1991-12-31 0 1992-06-30 30 1992-12-31 30 1993-06-30 41 1993-12-31 37 1994-06-30 39 1994-12-31 38 1995-06-30 21 1995-12-31 14 1996-06-30 75 1996-12-31 24 1997-06-30 12 1997-12-31 71 1998-06-30 28 1998-12-31 22 1999-06-30 33