Bi-annual US dollars 1987-06-30 113 1987-12-31 121 1988-06-30 29 1988-12-31 69 1989-06-30 33 1989-12-31 27 1990-06-30 21 1990-12-31 41 1991-06-30 45 1991-12-31 47 1992-06-30 40 1992-12-31 11 1993-06-30 11 1993-12-31 24 1994-06-30 22 1994-12-31 27 1995-06-30 16 1995-12-31 22 1996-06-30 30 1996-12-31 45 1997-06-30 43 1997-12-31 30 1998-06-30 63 1998-12-31 155 1999-06-30 151