Faith of rc, and a Opened larger than 1966 which has the highest DCSF number?
CREATE TABLE "berkhamsted" (
  "name" text,
  "faith" text,
  "type" text,
  "opened" real,
  "intake" real,
  "dcsf_number" real,
  "ofsted_number" real
);
SELECT MAX("dcsf_number") FROM "berkhamsted" WHERE "faith"='rc' AND "opened">1966;