Bi-annual US dollars 1987-06-30 232 1987-12-31 196 1988-06-30 181 1988-12-31 172 1989-06-30 180 1989-12-31 139 1990-06-30 164 1990-12-31 154 1991-06-30 128 1991-12-31 112 1992-06-30 107 1992-12-31 52 1993-06-30 86 1993-12-31 412 1994-06-30 451 1994-12-31 601 1995-06-30 625 1995-12-31 682 1996-06-30 590 1996-12-31 837 1997-06-30 950 1997-12-31 949 1998-06-30 1292 1998-12-31 1156 1999-06-30 1164