Bi-annual US dollars 1987-06-30 71 1987-12-31 77 1988-06-30 87 1988-12-31 92 1989-06-30 14 1989-12-31 73 1990-06-30 26 1990-12-31 19 1991-06-30 23 1991-12-31 19 1992-06-30 13 1992-12-31 14 1993-06-30 11 1993-12-31 24 1994-06-30 14 1994-12-31 22 1995-06-30 10 1995-12-31 11 1996-06-30 17 1996-12-31 22 1997-06-30 18 1997-12-31 18 1998-06-30 18 1998-12-31 13 1999-06-30 11