Bi-annual	US dollars
1987-06-30	876
1987-12-31	755
1988-06-30	650
1988-12-31	454
1989-06-30	412
1989-12-31	314
1990-06-30	326
1990-12-31	284
1991-06-30	269
1991-12-31	260
1992-06-30	270
1992-12-31	218
1993-06-30	260
1993-12-31	262
1994-06-30	236
1994-12-31	238
1995-06-30	200
1995-12-31	253
1996-06-30	365
1996-12-31	500
1997-06-30	679
1997-12-31	554
1998-06-30	1839
1998-12-31	1914
1999-06-30	941