text: 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_57 (year_joined__or_joining_ INTEGER, city VARCHAR)
  ### Question:
  What year did the team from City of Aurora join?
  ### Answer:
  SELECT AVG(year_joined__or_joining_) FROM table_name_57 WHERE city = "aurora"