What is the total number of goals that have games under 11, debut round over 15, and age of 20 years, 71 days?
CREATE TABLE "players_who_made_their_afl_debut_during_" (
  "name" text,
  "club" text,
  "age_at_debut" text,
  "debut_round" real,
  "games_2008" real,
  "goals_2008" real
);
SELECT COUNT("goals_2008") FROM "players_who_made_their_afl_debut_during_" WHERE "games_2008"<11 AND "debut_round">15 AND "age_at_debut"='20 years, 71 days';