Vertica 6.1 Backups Compressed or Uncompressed

I looked at the data per node and total in raw and compress at the system level.  Does the native Vertica backup, backups the data compressed or uncompressed?  Can we estimate the compressed size as the size of the full backup?

Following from the database...

     node_name     | size_in_bytes 
      -------------------+---------------
 v_demodb_node0001 |  105581123485
 v_demodb_node0004 |  105588178111
 v_demodb_node0002 |  105594415666
 v_demodb_node0003 |  105602856313
 
 
  anchor_table_schema |     used_gb      |      raw_gb      
---------------------+------------------+------------------
 test              |  317.69239487499 | 2553.13359010668
 test2            | 75.6671298583969 | 608.098569638268