Bi-annual	US dollars
1987-06-30	1450
1987-12-31	2138
1988-06-30	1796
1988-12-31	3135
1989-06-30	2902
1989-12-31	2982
1990-06-30	3537
1990-12-31	3124
1991-06-30	2771
1991-12-31	2437
1992-06-30	2685
1992-12-31	2810
1993-06-30	4881
1993-12-31	6605
1994-06-30	7537
1994-12-31	7076
1995-06-30	7590
1995-12-31	7196
1996-06-30	8222
1996-12-31	9193
1997-06-30	10080
1997-12-31	10226
1998-06-30	11843
1998-12-31	11066
1999-06-30	9730