Bi-annual	US dollars
1987-06-30	13813
1987-12-31	14413
1988-06-30	14906
1988-12-31	18391
1989-06-30	13741
1989-12-31	16219
1990-06-30	15675
1990-12-31	15793
1991-06-30	12928
1991-12-31	14933
1992-06-30	14360
1992-12-31	9507
1993-06-30	10337
1993-12-31	11969
1994-06-30	15418
1994-12-31	14579
1995-06-30	14588
1995-12-31	13525
1996-06-30	13531
1996-12-31	12778
1997-06-30	13893
1997-12-31	13556
1998-06-30	17432
1998-12-31	15883
1999-06-30	15505