Bi-annual US dollars 1987-06-30 218 1987-12-31 126 1988-06-30 94 1988-12-31 316 1989-06-30 126 1989-12-31 271 1990-06-30 134 1990-12-31 230 1991-06-30 172 1991-12-31 95 1992-06-30 126 1992-12-31 95 1993-06-30 129 1993-12-31 72 1994-06-30 94 1994-12-31 40 1995-06-30 48 1995-12-31 42 1996-06-30 57 1996-12-31 77 1997-06-30 140 1997-12-31 66 1998-06-30 93 1998-12-31 25 1999-06-30 14