Bi-annual US dollars 1987-06-30 248 1987-12-31 255 1988-06-30 213 1988-12-31 237 1989-06-30 243 1989-12-31 247 1990-06-30 258 1990-12-31 60 1991-06-30 105 1991-12-31 84 1992-06-30 49 1992-12-31 102 1993-06-30 420 1993-12-31 183 1994-06-30 69 1994-12-31 130 1995-06-30 118 1995-12-31 158 1996-06-30 143 1996-12-31 55 1997-06-30 143 1997-12-31 163 1998-06-30 148 1998-12-31 153 1999-06-30 129