Bi-annual	US dollars
1987-06-30	2141
1987-12-31	2104
1988-06-30	2616
1988-12-31	2256
1989-06-30	2057
1989-12-31	2000
1990-06-30	1805
1990-12-31	1108
1991-06-30	1093
1991-12-31	1522
1992-06-30	3760
1992-12-31	3551
1993-06-30	4380
1993-12-31	5325
1994-06-30	5653
1994-12-31	5230
1995-06-30	4935
1995-12-31	4487
1996-06-30	4998
1996-12-31	5410
1997-06-30	5643
1997-12-31	6334
1998-06-30	6017
1998-12-31	5766
1999-06-30	6637