Does the backup reports in OEM show the correct input size and output sizes of the RMAN backups?

Hi Friends,
What exactly is the Input Size mean? What exactly does output size mean?

Does the backup reports in OEM show the correct input size and output sizes of the RMAN backups?

I have a 1.4TB database(size pulled from dba_segments). We scheduled a weekly Incr 0 backup(Saturdays) and Incr 1 on the rest of the days. Block change tracking feature is NOT enabled.

I am confused about the input sizes shown in Backup Reports in OEM for this database.


Date                                       Level          Input Size    Output Size
July 06th 2013(saturday)      Incr 0        855.17G          172.57G
July 13th 2013(saturday)      Incr 0        850.92G          171.63G
July 20th 2013(saturday)      Incr 0        1.24T               249.43G