In what year was Yauco, which had over 42,043 people in 2010, founded?
CREATE TABLE "demographics" (
  "municipality" text,
  "fips_code" real,
  "founded" real,
  "population_2010" real,
  "area" text
);
SELECT AVG("founded") FROM "demographics" WHERE "municipality"='yauco' AND "population_2010">'42,043';