Bi-annual US dollars 1987-06-30 40 1987-12-31 30 1988-06-30 14 1988-12-31 22 1989-06-30 40 1989-12-31 18 1990-06-30 5 1990-12-31 21 1991-06-30 89 1991-12-31 7 1992-06-30 15 1992-12-31 67 1993-06-30 6 1993-12-31 34 1994-06-30 68 1994-12-31 196 1995-06-30 159 1995-12-31 107 1996-06-30 107 1996-12-31 24 1997-06-30 96 1997-12-31 87 1998-06-30 172 1998-12-31 45 1999-06-30 248