Different block count

why is the block count different between the 3 queries ? This is on 11203.

SYSTEM @ bsbc1_db06 > select count(distinct DBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID)) from CURAM_B1_USER.address;

COUNT(DISTINCTDBMS_ROWID.ROWID_BLOCK_NUMBER(ROWID))
---------------------------------------------------
                                               1002

SYSTEM @ bsbc1_db06 > select blocks from dba_tables where owner='CURAM_B1_USER' and table_name='ADDRESS';

    BLOCKS
----------
      1143

SYSTEM @ bsbc1_db06 > select blocks from dba_segments where owner='CURAM_B1_USER'
  2  and segment_type='TABLE'
  3  and segment_name='ADDRESS';

    BLOCKS
----------
      1152

Thanks