Bi-annual US dollars 1987-06-30 801 1987-12-31 587 1988-06-30 527 1988-12-31 466 1989-06-30 570 1989-12-31 411 1990-06-30 572 1990-12-31 392 1991-06-30 555 1991-12-31 779 1992-06-30 984 1992-12-31 729 1993-06-30 1855 1993-12-31 2746 1994-06-30 2498 1994-12-31 2836 1995-06-30 3013 1995-12-31 3427 1996-06-30 3289 1996-12-31 2773 1997-06-30 3161 1997-12-31 2966 1998-06-30 3453 1998-12-31 3331 1999-06-30 2395