user: Question: What was the date when the attendance was 77,918?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Game site', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, '2005-09-11', 'at Kansas City Chiefs', 'L 27–7', 'Arrowhead Stadium', '78,014']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Attendance" = '77,918';