Bi-annual	US dollars
1987-06-30	12826
1987-12-31	12596
1988-06-30	9784
1988-12-31	8707
1989-06-30	9914
1989-12-31	9161
1990-06-30	10978
1990-12-31	11234
1991-06-30	10827
1991-12-31	12187
1992-06-30	12208
1992-12-31	13200
1993-06-30	15101
1993-12-31	16401
1994-06-30	21225
1994-12-31	19639
1995-06-30	18826
1995-12-31	17773
1996-06-30	20130
1996-12-31	24023
1997-06-30	27943
1997-12-31	39161
1998-06-30	41017
1998-12-31	21632
1999-06-30	21566