What is every value for average on previous season if the competition is league two?
CREATE TABLE table_31304 (
    "Season" text,
    "Ave. Attendance" real,
    "+/- ave. on prev. season" text,
    "Competition" text,
    "Occupier" text
)
SELECT "+/- ave. on prev. season" FROM table_31304 WHERE "Competition" = 'League Two'
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 every value for average on previous season if the competition is league two? ### Input: CREATE TABLE table_31304 (
    "Season" text,
    "Ave. Attendance" real,
    "+/- ave. on prev. season" text,
    "Competition" text,
    "Occupier" text
) ### Response: SELECT "+/- ave. on prev. season" FROM table_31304 WHERE "Competition" = 'League Two'