user: Question: When did the team score 21 goals?
Columns: ['Goal', 'Date', 'Score', 'Result', 'Competition']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1.0, '20 November 1991', '1–0', '1–0', 'Euro 1992 qualifying']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Goal" = 21.0;