Bi-annual	US dollars
1987-06-30	1124
1987-12-31	1176
1988-06-30	1182
1988-12-31	1322
1989-06-30	1381
1989-12-31	1066
1990-06-30	1036
1990-12-31	1841
1991-06-30	1763
1991-12-31	1724
1992-06-30	1834
1992-12-31	1742
1993-06-30	1241
1993-12-31	1386
1994-06-30	1253
1994-12-31	1062
1995-06-30	1179
1995-12-31	1175
1996-06-30	1067
1996-12-31	967
1997-06-30	1015
1997-12-31	905
1998-06-30	950
1998-12-31	844
1999-06-30	831