Bi-annual US dollars 1987-06-30 79 1987-12-31 79 1988-06-30 19 1988-12-31 11 1989-06-30 19 1989-12-31 18 1990-06-30 14 1990-12-31 14 1991-06-30 21 1991-12-31 2 1992-06-30 19 1992-12-31 48 1993-06-30 66 1993-12-31 56 1994-06-30 54 1994-12-31 59 1995-06-30 76 1995-12-31 37 1996-06-30 93 1996-12-31 12 1997-06-30 10 1997-12-31 3 1998-06-30 47 1998-12-31 57 1999-06-30 16