What is the lowest win percentage for when Perth Scorchers is the opposition?
CREATE TABLE "result_summary_in_champions_league" (
  "opposition" text,
  "span" text,
  "lost" real,
  "tied" real,
  "win_pct" real
);
SELECT MIN("win_pct") FROM "result_summary_in_champions_league" WHERE "opposition"='perth scorchers';