Bi-annual	US dollars
1987-06-30	974
1987-12-31	753
1988-06-30	704
1988-12-31	812
1989-06-30	756
1989-12-31	877
1990-06-30	799
1990-12-31	633
1991-06-30	694
1991-12-31	573
1992-06-30	502
1992-12-31	397
1993-06-30	641
1993-12-31	683
1994-06-30	613
1994-12-31	659
1995-06-30	550
1995-12-31	493
1996-06-30	441
1996-12-31	556
1997-06-30	712
1997-12-31	691
1998-06-30	727
1998-12-31	616
1999-06-30	454