Write SQL query to solve given problem: Among the flights departing from John F. Kennedy International, how many of them arrived earlier than scheduled?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT SUM(CASE WHEN T2.ARR_DELAY < 0 THEN 1 ELSE 0 END) AS count FROM Airports AS T1 INNER JOIN Airlines AS T2 ON T1.Code = T2.ORIGIN WHERE T1.Description = 'New York, NY: John F. Kennedy International'