What is the year the institution Tougaloo College joined?
CREATE TABLE "current_members" (
  "institution" text,
  "location" text,
  "mens_nickname" text,
  "womens_nickname" text,
  "founded" real,
  "type" text,
  "enrollment" real,
  "joined" text
);
SELECT "joined" FROM "current_members" WHERE "institution"='Tougaloo College';