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_56 (year INTEGER, power VARCHAR)
### Question:
When is the earliest year with a Power of 90kw (121hp) @ 4000?
### Answer:
SELECT MIN(year) FROM table_name_56 WHERE power = "90kw (121hp) @ 4000"