Bi-annual	US dollars
1987-06-30	5720
1987-12-31	6195
1988-06-30	5768
1988-12-31	6021
1989-06-30	6061
1989-12-31	6240
1990-06-30	5637
1990-12-31	5152
1991-06-30	4772
1991-12-31	5433
1992-06-30	7186
1992-12-31	8187
1993-06-30	9413
1993-12-31	8309
1994-06-30	8361
1994-12-31	9597
1995-06-30	9790
1995-12-31	10598
1996-06-30	11707
1996-12-31	13054
1997-06-30	15348
1997-12-31	20339
1998-06-30	18997
1998-12-31	18692
1999-06-30	18633