Bi-annual US dollars 1987-06-30 129 1987-12-31 177 1988-06-30 143 1988-12-31 76 1989-06-30 180 1989-12-31 214 1990-06-30 204 1990-12-31 95 1991-06-30 183 1991-12-31 155 1992-06-30 160 1992-12-31 242 1993-06-30 161 1993-12-31 208 1994-06-30 145 1994-12-31 156 1995-06-30 62 1995-12-31 70 1996-06-30 245 1996-12-31 185 1997-06-30 118 1997-12-31 87 1998-06-30 57 1998-12-31 324 1999-06-30 43