Position of defensive tackle, and a Round of 4, and a Pick # smaller than 36 has what overall average?
CREATE TABLE "indianapolis_colts_draft_history" (
  "round" real,
  "pick_num" real,
  "overall" real,
  "name" text,
  "position" text,
  "college" text
);
SELECT AVG("overall") FROM "indianapolis_colts_draft_history" WHERE "position"='defensive tackle' AND "round"=4 AND "pick_num"<36;