CREATE TABLE "historical_rankings" (
  "year" real,
  "political_rights" real,
  "civil_liberties" real,
  "status" text,
  "president" text
);

Question: When the president was Yoweri Museveni, and the year was 1993, with rank of 6 under political rights, what was the total of civil liberties?
SQL: SELECT SUM("civil_liberties") FROM "historical_rankings" WHERE "political_rights"=6 AND "president"='yoweri museveni' AND "year"=1993;

Question: What is the year average when not free was the status, and less than 7 was the civil liberties, and less than 6 political rights?
SQL: SELECT AVG("year") FROM "historical_rankings" WHERE "status"='not free' AND "civil_liberties"<7 AND "political_rights"<6;

Question: What is the least political rights rank in 1976?
SQL: SELECT MIN("political_rights") FROM "historical_rankings" WHERE "year"=1976;