Bi-annual	US dollars
1987-06-30	837
1987-12-31	751
1988-06-30	819
1988-12-31	833
1989-06-30	715
1989-12-31	824
1990-06-30	910
1990-12-31	722
1991-06-30	1044
1991-12-31	953
1992-06-30	1106
1992-12-31	544
1993-06-30	1143
1993-12-31	649
1994-06-30	702
1994-12-31	638
1995-06-30	558
1995-12-31	578
1996-06-30	592
1996-12-31	743
1997-06-30	850
1997-12-31	768
1998-06-30	585
1998-12-31	278
1999-06-30	527