What is the lowest number of members lost when the  net change is −1?
CREATE TABLE "ice_hockey" (
  "conference" text,
  "old_membership_total" real,
  "new_membership_total" real,
  "net_change" text,
  "members_added" real,
  "members_lost" real
);
SELECT MIN("members_lost") FROM "ice_hockey" WHERE "net_change"='−1';