What are the years that "WiiU" got a new game?
year refers to release_year; "WiiU" refers to platform_name = 'WiiU'
SELECT T2.release_year FROM platform AS T1 INNER JOIN game_platform AS T2 ON T1.id = T2.platform_id WHERE T1.platform_name = 'WiiU' ORDER BY T2.release_year DESC LIMIT 1