Bi-annual US dollars 1987-06-30 23 1987-12-31 26 1988-06-30 19 1988-12-31 16 1989-06-30 11 1989-12-31 13 1990-06-30 10 1990-12-31 15 1991-06-30 10 1991-12-31 21 1992-06-30 10 1992-12-31 8 1993-06-30 14 1993-12-31 7 1994-06-30 19 1994-12-31 8 1995-06-30 5 1995-12-31 6 1996-06-30 11 1996-12-31 7 1997-06-30 7 1997-12-31 2 1998-06-30 2 1998-12-31 2 1999-06-30 0