What is the lowest amount of floors in the building completed before 1970 ranked more than 14?
CREATE TABLE "buildings_completed_as_of_february_2011" (
  "rank" real,
  "building" text,
  "height" text,
  "floors" real,
  "completed" real
);
SELECT MIN("floors") FROM "buildings_completed_as_of_february_2011" WHERE "completed"<1970 AND "rank">14;