Table schema:
CREATE TABLE table_name_84 (points INTEGER, attendance VARCHAR, home VARCHAR, date VARCHAR)

Question: What is the sum of Points, when Home is "Pittsburgh", when Date is "December 21", and when Attendance is greater than 5,307?
SQL: SELECT SUM(points) FROM table_name_84 WHERE home = "pittsburgh" AND date = "december 21" AND attendance > 5 OFFSET 307