What is the Height (m) of the 32= Rank Building with 18 Floors and Height (ft) greater than 171?
CREATE TABLE "tallest_completed_buildings_and_structur" (
  "rank" text,
  "name" text,
  "height_m" real,
  "height_ft" real,
  "floors" text
);
SELECT AVG("height_m") FROM "tallest_completed_buildings_and_structur" WHERE "floors"='18' AND "height_ft">171 AND "rank"='32=';