user: Question: Mean attendance for December 22, 1980?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'September 7, 1980', 'at Seattle Seahawks', 'W 34-13', 62042.0]
SQL:

assistant: SELECT AVG("Attendance") FROM "Table" WHERE "Date" = 'December 22, 1980';