Which Pct has Years of 1957–1970, and Wins smaller than 78?
CREATE TABLE "head_coaching_history" (
  "name" text,
  "years" text,
  "wins" real,
  "losses" real,
  "ties" real,
  "pct" real
);
SELECT SUM("pct") FROM "head_coaching_history" WHERE "years"='1957–1970' AND "wins"<78;