Bi-annual	US dollars
1987-06-30	18
1987-12-31	25
1988-06-30	29
1988-12-31	27
1989-06-30	25
1989-12-31	26
1990-06-30	23
1990-12-31	23
1991-06-30	16
1991-12-31	17
1992-06-30	25
1992-12-31	21
1993-06-30	21
1993-12-31	19
1994-06-30	32
1994-12-31	36
1995-06-30	38
1995-12-31	43
1996-06-30	51
1996-12-31	60
1997-06-30	53
1997-12-31	51
1998-06-30	48
1998-12-31	43
1999-06-30	41