Bi-annual US dollars 1987-06-30 124 1987-12-31 85 1988-06-30 72 1988-12-31 80 1989-06-30 16 1989-12-31 77 1990-06-30 49 1990-12-31 91 1991-06-30 11 1991-12-31 28 1992-06-30 15 1992-12-31 74 1993-06-30 236 1993-12-31 46 1994-06-30 71 1994-12-31 74 1995-06-30 52 1995-12-31 53 1996-06-30 85 1996-12-31 94 1997-06-30 96 1997-12-31 105 1998-06-30 7 1998-12-31 178 1999-06-30 137