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_15555661_2 (area__km²_ VARCHAR, ecozone VARCHAR)
### Question:
How large is the Boreal Shield in km2?
### Answer:
SELECT COUNT(area__km²_) FROM table_15555661_2 WHERE ecozone = "Boreal Shield"