Bi-annual	US dollars
1987-06-30	12156
1987-12-31	13321
1988-06-30	12873
1988-12-31	13920
1989-06-30	12820
1989-12-31	12741
1990-06-30	13151
1990-12-31	12471
1991-06-30	12935
1991-12-31	14239
1992-06-30	14704
1992-12-31	14494
1993-06-30	18267
1993-12-31	18870
1994-06-30	21710
1994-12-31	21664
1995-06-30	22271
1995-12-31	26312
1996-06-30	26528
1996-12-31	26087
1997-06-30	12119
1997-12-31	14839
1998-06-30	0
1998-12-31	0
1999-06-30	0