What is the lowest percentage of wins for 6½ games and more than 77 total wins?
CREATE TABLE "regular_season_results" (
  "season" text,
  "wins" real,
  "losses" real,
  "winpct" real,
  "games_behind" text,
  "playoffs" text,
  "results" text
);
SELECT MIN("winpct") FROM "regular_season_results" WHERE "games_behind"='6½' AND "wins">77;