Bi-annual US dollars 1987-06-30 48 1987-12-31 38 1988-06-30 32 1988-12-31 11 1989-06-30 3 1989-12-31 0 1990-06-30 0 1990-12-31 0 1991-06-30 0 1991-12-31 0 1992-06-30 0 1992-12-31 26 1993-06-30 26 1993-12-31 28 1994-06-30 0 1994-12-31 28 1995-06-30 27 1995-12-31 45 1996-06-30 51 1996-12-31 62 1997-06-30 68 1997-12-31 77 1998-06-30 87 1998-12-31 58 1999-06-30 66