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_74 (post_position INTEGER, lengths_behind VARCHAR)
### Question:
What's the post position when the lengths behind is 0?
### Answer:
SELECT AVG(post_position) FROM table_name_74 WHERE lengths_behind = "0"