mtime to remove old files

[leprod:> ls -la /dbdumps/backups/df*

-rw-r----- 1 oracle dba 5256142848 Sep 18 07:12 /dbdumps/backups/df_t51

When I use:

[leprod:> find /dbdumps/backups -name "df*" -mtime +0 -print
/dbdumps/backups/df_t537174441_s1_p1
[oracle_at_dohsdb10]:/usr/oracle/tools/bin

When I use anything other than +1 or more the file isn't found. However, the system date is Sep 20. Yet the last modified time was the 18th. =20

What am I missing?

--
http://www.freelists.org/webpage/oracle-l