Bi-annual	US dollars
1987-06-30	1358
1987-12-31	1372
1988-06-30	1334
1988-12-31	1331
1989-06-30	1164
1989-12-31	909
1990-06-30	736
1990-12-31	735
1991-06-30	640
1991-12-31	665
1992-06-30	620
1992-12-31	385
1993-06-30	563
1993-12-31	495
1994-06-30	468
1994-12-31	390
1995-06-30	447
1995-12-31	414
1996-06-30	614
1996-12-31	820
1997-06-30	1111
1997-12-31	1357
1998-06-30	1417
1998-12-31	1364
1999-06-30	1515