CREATE TABLE "attendances" (
  "season" real,
  "average_attendance_home" real,
  "highest_attendance_home" text,
  "average_attendance_away" real,
  "highest_attendance_away" text,
  "division_section" text,
  "level" text,
  "average_attendance_league" real
);

Question: How many season have an average attendance league of 2.456?
SQL: SELECT SUM("season") FROM "attendances" WHERE "average_attendance_league"=2.456;