What is the population (2008) when the capital was Sanniquellie, created later than 1964?
CREATE TABLE "counties_and_districts" (
  "mapnum" real,
  "county" text,
  "capital" text,
  "population_2008" real,
  "area" text,
  "created" real
);
SELECT SUM("population_2008") FROM "counties_and_districts" WHERE "capital"='sanniquellie' AND "created">1964;