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_68 (_percentage_change VARCHAR, airport VARCHAR)
### Question:
What is the % Change at London Heathrow airport?
### Answer:
SELECT _percentage_change FROM table_name_68 WHERE airport = "london heathrow airport"