Bi-annual	US dollars
1987-06-30	2088
1987-12-31	2893
1988-06-30	2753
1988-12-31	2817
1989-06-30	3434
1989-12-31	3209
1990-06-30	3423
1990-12-31	3589
1991-06-30	2424
1991-12-31	2211
1992-06-30	2565
1992-12-31	2888
1993-06-30	2488
1993-12-31	1944
1994-06-30	3431
1994-12-31	3657
1995-06-30	4562
1995-12-31	2937
1996-06-30	2231
1996-12-31	2684
1997-06-30	2903
1997-12-31	3526
1998-06-30	3650
1998-12-31	3736
1999-06-30	3494