What is the average number of losses for teams with 0 draws and 0 byes?
CREATE TABLE "2010_ladder" (
  "ntfa_div_1" text,
  "wins" real,
  "byes" real,
  "losses" real,
  "draws" real,
  "against" real
);
SELECT AVG("losses") FROM "2010_ladder" WHERE "draws"=0 AND "byes"<0;