Bi-annual US dollars 1987-06-30 490 1987-12-31 1119 1988-06-30 877 1988-12-31 835 1989-06-30 674 1989-12-31 956 1990-06-30 516 1990-12-31 542 1991-06-30 263 1991-12-31 616 1992-06-30 324 1992-12-31 392 1993-06-30 1253 1993-12-31 941 1994-06-30 940 1994-12-31 2231 1995-06-30 934 1995-12-31 1817 1996-06-30 1263 1996-12-31 1496 1997-06-30 1286 1997-12-31 304 1998-06-30 1697 1998-12-31 504 1999-06-30 885