Bi-annual	US dollars
1987-06-30	1034
1987-12-31	1042
1988-06-30	1098
1988-12-31	1119
1989-06-30	1133
1989-12-31	1148
1990-06-30	1577
1990-12-31	1592
1991-06-30	1947
1991-12-31	1593
1992-06-30	1507
1992-12-31	1635
1993-06-30	1850
1993-12-31	1001
1994-06-30	1978
1994-12-31	2278
1995-06-30	1059
1995-12-31	884
1996-06-30	2105
1996-12-31	1286
1997-06-30	607
1997-12-31	2451
1998-06-30	4265
1998-12-31	2210
1999-06-30	2003