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_18 (best_fit__all_data_ VARCHAR, parameter VARCHAR)
### Question:
What is the best fit (all data) when the parameter shows fluctuation amplitude at 8h −1 mpc?
### Answer:
SELECT best_fit__all_data_ FROM table_name_18 WHERE parameter = "fluctuation amplitude at 8h −1 mpc"