What is the percentage of the cost for the game events?
game events refers to type = 'Game'; percentage = DIVIDE( SUM(cost), COUNT(event_id)) * 100
SELECT SUM(CASE WHEN T1.type = 'Game' THEN T3.cost ELSE 0 END) * 100 / SUM(T3.cost) FROM event AS T1 INNER JOIN budget AS T2 ON T1.event_id = T2.link_to_event INNER JOIN expense AS T3 ON T2.budget_id = T3.link_to_budget