Bi-annual	US dollars
1987-06-30	295
1987-12-31	313
1988-06-30	484
1988-12-31	689
1989-06-30	870
1989-12-31	866
1990-06-30	879
1990-12-31	971
1991-06-30	801
1991-12-31	969
1992-06-30	1315
1992-12-31	889
1993-06-30	2092
1993-12-31	2295
1994-06-30	2469
1994-12-31	3052
1995-06-30	3207
1995-12-31	3551
1996-06-30	4506
1996-12-31	5704
1997-06-30	6906
1997-12-31	8177
1998-06-30	7798
1998-12-31	6508
1999-06-30	5809