Bi-annual	US dollars
1987-06-30	149089
1987-12-31	161238
1988-06-30	154247
1988-12-31	149988
1989-06-30	151307
1989-12-31	152654
1990-06-30	154810
1990-12-31	160149
1991-06-30	142648
1991-12-31	155728
1992-06-30	159774
1992-12-31	156056
1993-06-30	220662
1993-12-31	226156
1994-06-30	232355
1994-12-31	266929
1995-06-30	280157
1995-12-31	286066
1996-06-30	302452
1996-12-31	329092
1997-06-30	367364
1997-12-31	411978
1998-06-30	439939
1998-12-31	417939
1999-06-30	411710