user: Question: What was the crowd size when the visiting team scored 23.18 (156)?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Melbourne', '17.9 (111)', 'North Melbourne', '23.18 (156)', 'MCG', 23261.0, '2 June 1979']
SQL:

assistant: SELECT "Crowd" FROM "Table" WHERE "Away team score" = '23.18 (156)';