Bi-annual	US dollars
1987-06-30	722
1987-12-31	834
1988-06-30	756
1988-12-31	855
1989-06-30	1085
1989-12-31	1037
1990-06-30	1212
1990-12-31	1082
1991-06-30	1163
1991-12-31	1300
1992-06-30	1239
1992-12-31	1154
1993-06-30	1371
1993-12-31	1463
1994-06-30	1392
1994-12-31	1342
1995-06-30	1039
1995-12-31	923
1996-06-30	952
1996-12-31	930
1997-06-30	1058
1997-12-31	956
1998-06-30	957
1998-12-31	1340
1999-06-30	949