user: Question: What is the average crowd attendance for Collingwood?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Footscray', '18.11 (119)', 'North Melbourne', '11.18 (84)', 'Western Oval', 13000.0, '27 August 1938']
SQL:

assistant: SELECT AVG("Crowd") FROM "Table" WHERE "Home team" = 'Collingwood';