Bi-annual US dollars 1987-06-30 13 1987-12-31 42 1988-06-30 46 1988-12-31 34 1989-06-30 60 1989-12-31 69 1990-06-30 58 1990-12-31 56 1991-06-30 50 1991-12-31 52 1992-06-30 49 1992-12-31 86 1993-06-30 152 1993-12-31 101 1994-06-30 93 1994-12-31 91 1995-06-30 99 1995-12-31 79 1996-06-30 126 1996-12-31 159 1997-06-30 190 1997-12-31 150 1998-06-30 208 1998-12-31 220 1999-06-30 765