Write SQL query to solve given problem: Among all closed businesses in Avondale, AZ what percent have obtained a 'wonderful experience' rating of the business.. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT CAST(SUM(CASE WHEN stars > 3 THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(stars) FROM Business WHERE city = 'Avondale' AND active = 'false'