Below is an context that describes a sql query, paired with an question that provides further information. Write an answer that appropriately completes the request.  # noqa: E501
### Context:
CREATE TABLE table_name_81 (year INTEGER, points VARCHAR, class VARCHAR, team VARCHAR)
### Question:
In what Year did the Norton Team have 0 Points and 350cc Class?
### Answer:
SELECT AVG(year) FROM table_name_81 WHERE class = "350cc" AND team = "norton" AND points < 0