What is the Win % in the Span of 2011–2013 with a Lost of less than 1?
CREATE TABLE "result_summary" (
  "opposition" text,
  "span" text,
  "lost" real,
  "tied" real,
  "win_pct" real
);
SELECT AVG("win_pct") FROM "result_summary" WHERE "span"='2011–2013' AND "lost"<1;