user: Question: What is the average Margin that has a Round of 13. (H)?
Columns: ['Round', 'St Kilda Saints', 'Opposition', 'Their Score', 'Margin']
Types: ['text', 'text', 'text', 'text', 'real']
Sample row: ['1. (H)', '6.15 (51)', 'Sydney', '6.13 (49)', 2.0]
SQL:

assistant: SELECT AVG("Margin") FROM "Table" WHERE "Round" = '13. (H)';