What is the average 2006 metropolitan population of Lima with a GDP per capita over $13,100?
CREATE TABLE "population_and_economy_size_for_latin_am" (
  "rank" real,
  "metropolitan_area" text,
  "country" text,
  "gdp_ppp_2008_billions_of_us" real,
  "metropolitan_population_2006_millions" real,
  "gdp_ppp_us_per_capita" real
);
SELECT AVG("metropolitan_population_2006_millions") FROM "population_and_economy_size_for_latin_am" WHERE "metropolitan_area"='lima' AND "gdp_ppp_us_per_capita">'13,100';