CREATE TABLE table_13836704_4 (total_passengers_2008 INT, change_2008_09 VARCHAR)

what being the maximum total passengers 2008 with change 2008/09 being 6.5%
SELECT MAX(total_passengers_2008) FROM table_13836704_4 WHERE change_2008_09 = "6.5%"
SELECT MAX("total_passengers_2008") FROM "table_13836704_4" WHERE "6.5%" = "change_2008_09"