user: Question: When the away team score was 11.5 (71), what was the date?
Columns: ['Home team', 'Home team score', 'Away team', 'Away team score', 'Venue', 'Crowd', 'Date']
Types: ['text', 'text', 'text', 'text', 'text', 'real', 'text']
Sample row: ['Richmond', '12.18 (90)', 'South Melbourne', '11.13 (79)', 'MCG', 22870.0, '10 July 1971']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Away team score" = '11.5 (71)';