Bi-annual US dollars 1987-06-30 163 1987-12-31 187 1988-06-30 177 1988-12-31 184 1989-06-30 166 1989-12-31 185 1990-06-30 150 1990-12-31 199 1991-06-30 175 1991-12-31 177 1992-06-30 141 1992-12-31 108 1993-06-30 102 1993-12-31 58 1994-06-30 59 1994-12-31 25 1995-06-30 30 1995-12-31 22 1996-06-30 37 1996-12-31 48 1997-06-30 48 1997-12-31 54 1998-06-30 67 1998-12-31 50 1999-06-30 39