user: ### NOW ANSWER:
Question: What was the Attendance on december 21, 1986 before Week 16?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'September 7, 1986', 'at Kansas City Chiefs', 'L 24–14', 43430.0]
SQL:

assistant: SELECT SUM("Attendance") FROM "Table" WHERE "Date" = 'december 21, 1986' AND "Week" < 16.0;