After December 19, what is the Game number with a Record of 21–4–7?
CREATE TABLE "regular_season" (
  "game" real,
  "december" real,
  "opponent" text,
  "score" text,
  "record" text,
  "points" real
);
SELECT COUNT("game") FROM "regular_season" WHERE "record"='21–4–7' AND "december">19;