Table schema:
CREATE TABLE table_name_21 (ties INTEGER, games_played VARCHAR, wins VARCHAR, goals_against VARCHAR)

Question: For teams with fewer than 5 wins, goals against over 37, and fewer than 8 games played, what is the average number of ties?
SQL: SELECT AVG(ties) FROM table_name_21 WHERE wins < 5 AND goals_against > 37 AND games_played < 8