Question: What is the percentage of flights from Los Angeles International airport that were cancelled due to a type C cancellation code?
SQL: SELECT CAST(SUM(CASE WHEN T2.CANCELLATION_CODE = 'C' THEN 1.0 ELSE 0 END) AS REAL) * 100 / COUNT(*) FROM Airports AS T1 INNER JOIN Airlines AS T2 ON T1.Code = T2.ORIGIN WHERE T2.FL_DATE = '2018/8/15' AND T2.CANCELLATION_CODE IS NOT NULL AND T1.Description = 'Los Angeles, CA: Los Angeles International'