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_8 (sites INTEGER, screens VARCHAR, rank VARCHAR)
### Question:
what is the number of sites when the number of screens is 687 and rank is more than 7?
### Answer:
SELECT AVG(sites) FROM table_name_8 WHERE screens = 687 AND rank > 7