Bi-annual	US dollars
1987-06-30	274
1987-12-31	255
1988-06-30	249
1988-12-31	344
1989-06-30	330
1989-12-31	376
1990-06-30	283
1990-12-31	297
1991-06-30	255
1991-12-31	295
1992-06-30	289
1992-12-31	251
1993-06-30	287
1993-12-31	387
1994-06-30	358
1994-12-31	368
1995-06-30	385
1995-12-31	366
1996-06-30	337
1996-12-31	372
1997-06-30	363
1997-12-31	387
1998-06-30	444
1998-12-31	384
1999-06-30	330