What's the population that has a median family income of $50,553?
CREATE TABLE "texas_counties_ranked_by_per_capita_inco" (
  "county" text,
  "per_capita_income" text,
  "median_household_income" text,
  "median_family_income" text,
  "population" real,
  "number_of_households" real
);
SELECT COUNT("population") FROM "texas_counties_ranked_by_per_capita_inco" WHERE "median_family_income"='$50,553';