Bi-annual US dollars 1987-06-30 240 1987-12-31 302 1988-06-30 293 1988-12-31 367 1989-06-30 350 1989-12-31 379 1990-06-30 473 1990-12-31 654 1991-06-30 1033 1991-12-31 902 1992-06-30 797 1992-12-31 644 1993-06-30 639 1993-12-31 656 1994-06-30 636 1994-12-31 993 1995-06-30 1079 1995-12-31 1071 1996-06-30 1005 1996-12-31 2044 1997-06-30 2055 1997-12-31 2257 1998-06-30 2283 1998-12-31 2674 1999-06-30 2116