Question: Among the trains that have at least one non-regular shaped car, what is the percentage of it running in the east direction?
SQL: SELECT CAST(COUNT(DISTINCT CASE WHEN T2.direction = 'east' THEN T1.train_id ELSE NULL END) AS REAL) * 100 / COUNT(DISTINCT T1.train_id) FROM cars AS T1 INNER JOIN trains AS T2 ON T1.train_id = T2.id WHERE T1.shape IN ('bucket', 'ellipse')