Write SQL query to solve given problem: In episodes aired in 2009, how many of them are credited to Sam Im for additional timer?. Keep the solution inside sql tag ```sql [SQL-Query] ```
SELECT COUNT(*) FROM Episode AS T1 INNER JOIN Credit AS T2 ON T1.episode_id = T2.episode_id WHERE T2.credited = 'true' AND T2.person = 'Sam Im' AND SUBSTR(T1.air_date, 1, 4) = '2009' AND T2.role = 'additional timer';