diff --git a/mysqldb-backup.sh b/mysqldb-backup.sh
index 98989aa..c1843da 100644
--- a/mysqldb-backup.sh
+++ b/mysqldb-backup.sh
@@ -41,6 +41,6 @@ chown $STOR_USER $TMPDIR/database-$NOW.tar.gz
 mv $TMPDIR/database-$NOW.tar.gz $STOR
 
 # delete old files in storage
-find $STOR -mtime $STOR_DAYS -exec rm {} \;
+find $STOR -mtime +$STOR_DAYS -exec rm {} \;
 
 rm -rf $TMPDIR