What is the decile sum with a roll smaller than 25, and franz josef area?
CREATE TABLE "westland_district" (
  "name" text,
  "years" text,
  "area" text,
  "authority" text,
  "decile" real,
  "roll" real
);
SELECT SUM("decile") FROM "westland_district" WHERE "roll"<25 AND "area"='franz josef';