What is the completion percentage when yards per attempt was done by Steve McNair : 2003?
CREATE TABLE table_19517448_3 (
    completion_percentage VARCHAR,
    yards_per_attempt VARCHAR
)
SELECT completion_percentage FROM table_19517448_3 WHERE yards_per_attempt = "Steve McNair : 2003"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: What is the completion percentage when yards per attempt was done by Steve McNair : 2003? ### Input: CREATE TABLE table_19517448_3 (
    completion_percentage VARCHAR,
    yards_per_attempt VARCHAR
) ### Response: SELECT completion_percentage FROM table_19517448_3 WHERE yards_per_attempt = "Steve McNair : 2003"