user: Question: What is the average year of the games with the date December 26?
Columns: ['Year', 'Date', 'Winner', 'Result', 'Loser', 'Location']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1990.0, 'November 4', 'Kansas City Chiefs', '9–7', 'Los Angeles Raiders', 'Arrowhead Stadium']
SQL:

assistant: SELECT AVG("Year") FROM "Table" WHERE "Date" = 'December 26';