how many high schools had a league leave to big nine conference ?
CREATE TABLE table_203_591 (
    id number,
    "high school" text,
    "join\nyear" text,
    "from" text,
    "left" text,
    "league left to" text
)
SELECT COUNT("high school") FROM table_203_591 WHERE "league left to" = 'big nine conference'
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: how many high schools had a league leave to big nine conference ? ### Input: CREATE TABLE table_203_591 (
    id number,
    "high school" text,
    "join\nyear" text,
    "from" text,
    "left" text,
    "league left to" text
) ### Response: SELECT COUNT("high school") FROM table_203_591 WHERE "league left to" = 'big nine conference'