user: Question: Which duration was defeated by retired?
Columns: ['Name', 'Wins', 'Start', 'Duration', 'Defeated by']
Types: ['text', 'real', 'text', 'text', 'text']
Sample row: ['Sakumayama', 27.0, '2nd day July 2011', '6 months 12 days', 'Senshō']
SQL:

assistant: SELECT "Duration" FROM "Table" WHERE "Defeated by" = 'retired';