Bi-annual US dollars 1987-06-30 5 1987-12-31 6 1988-06-30 0 1988-12-31 2 1989-06-30 5 1989-12-31 18 1990-06-30 14 1990-12-31 29 1991-06-30 15 1991-12-31 24 1992-06-30 11 1992-12-31 24 1993-06-30 32 1993-12-31 31 1994-06-30 34 1994-12-31 38 1995-06-30 38 1995-12-31 26 1996-06-30 5 1996-12-31 7 1997-06-30 40 1997-12-31 20 1998-06-30 18 1998-12-31 33 1999-06-30 54