Among all closed businesses in Avondale, AZ what percent have obtained a 'wonderful experience' rating of the business.
closed business refers to active = 'false'; in Avondale refers to city = 'Avondale'; 'wonderful experience' rating refers to stars > 3; percentage = divide(count(business_id where stars > 3), count(business_id))*100%
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'