What's the average area for the xinluo district?
CREATE TABLE "administration" (
  "english_name" text,
  "simplified" text,
  "traditional" text,
  "pinyin" text,
  "hakka" text,
  "area" real,
  "population" real,
  "density" real
);
SELECT AVG("area") FROM "administration" WHERE "english_name"='xinluo district';