user: ### NOW ANSWER:
Question: What was the attendance on September 11, 1988?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'September 4, 1988', 'Seattle Seahawks', 'L 21–14', 75986.0]
SQL:

assistant: SELECT AVG("Attendance") FROM "Table" WHERE "Date" = 'September 11, 1988';