What is the average rank of the record on 2007-06-21 with a mark less than 91.29?
CREATE TABLE "men_s_best_throwers_of_all_time_current_" (
  "rank" real,
  "mark" real,
  "athlete" text,
  "place" text,
  "date" text
);
SELECT AVG("rank") FROM "men_s_best_throwers_of_all_time_current_" WHERE "date"='2007-06-21' AND "mark"<91.29;