This screenshot shows the Undo Advisor region of the Undo Management page. It displays a XY coordinate graph with the following values:
When Undo Retention Times = 500, Undo Tablespace Size = 19 MB.
When Undo Retention Times increases from 750 to 4,000 the Undo Tablespace Size remains constant at Target which is 23 MB for 1,500 Undo Retentions.
An increase of 2 MB takes places at 4,000 until 5,000 times.