What was the manner of depature when the date of appointment was 27 December 2007?
CREATE TABLE "managerial_changes" (
  "team" text,
  "outgoing_manager" text,
  "manner_of_departure" text,
  "date_of_vacancy" text,
  "replaced_by" text,
  "date_of_appointment" text
);
SELECT "manner_of_departure" FROM "managerial_changes" WHERE "date_of_appointment"='27 december 2007';