Bi-annual	US dollars
1987-06-30	385
1987-12-31	455
1988-06-30	790
1988-12-31	928
1989-06-30	991
1989-12-31	1114
1990-06-30	1416
1990-12-31	2043
1991-06-30	1644
1991-12-31	2327
1992-06-30	2072
1992-12-31	2016
1993-06-30	2347
1993-12-31	1763
1994-06-30	1897
1994-12-31	2051
1995-06-30	2475
1995-12-31	2098
1996-06-30	2287
1996-12-31	2208
1997-06-30	2262
1997-12-31	3340
1998-06-30	3855
1998-12-31	4601
1999-06-30	3521