What is the average Poles, when Wins is 0, when Position is "nc", and when Season is before 2004?
CREATE TABLE "career_summary" (
  "season" real,
  "wins" real,
  "poles" real,
  "podiums" real,
  "position" text
);
SELECT AVG("poles") FROM "career_summary" WHERE "wins"=0 AND "position"='nc' AND "season"<2004;