Bi-annual	US dollars
1987-06-30	6872
1987-12-31	6576
1988-06-30	7032
1988-12-31	8145
1989-06-30	8197
1989-12-31	8988
1990-06-30	8894
1990-12-31	10305
1991-06-30	10421
1991-12-31	11801
1992-06-30	11882
1992-12-31	11038
1993-06-30	11212
1993-12-31	12579
1994-06-30	10887
1994-12-31	13547
1995-06-30	12888
1995-12-31	12759
1996-06-30	11362
1996-12-31	14283
1997-06-30	14681
1997-12-31	15556
1998-06-30	19331
1998-12-31	20186
1999-06-30	21238