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_55 (year INTEGER, mixed_doubles VARCHAR)
  ### Question:
  When did mika heinonen susanna dahlberg win mixed doubles?
  ### Answer:
  SELECT AVG(year) FROM table_name_55 WHERE mixed_doubles = "mika heinonen susanna dahlberg"