Bi-annual US dollars 1987-06-30 6 1987-12-31 13 1988-06-30 7 1988-12-31 7 1989-06-30 14 1989-12-31 11 1990-06-30 16 1990-12-31 19 1991-06-30 21 1991-12-31 19 1992-06-30 17 1992-12-31 20 1993-06-30 17 1993-12-31 19 1994-06-30 11 1994-12-31 3 1995-06-30 0 1995-12-31 0 1996-06-30 0 1996-12-31 0 1997-06-30 0 1997-12-31 0 1998-06-30 0 1998-12-31 0 1999-06-30 0