Bi-annual US dollars 1987-06-30 19 1987-12-31 17 1988-06-30 19 1988-12-31 24 1989-06-30 2 1989-12-31 10 1990-06-30 16 1990-12-31 0 1991-06-30 2 1991-12-31 17 1992-06-30 8 1992-12-31 18 1993-06-30 56 1993-12-31 33 1994-06-30 57 1994-12-31 47 1995-06-30 56 1995-12-31 45 1996-06-30 23 1996-12-31 103 1997-06-30 101 1997-12-31 165 1998-06-30 372 1998-12-31 311 1999-06-30 279