In 2011, how many tourists visited the country that had 23.4 million tourists in 2012?
CREATE TABLE "the_americas" (
  "rank" real,
  "country" text,
  "international_tourist_arrivals_2012" text,
  "international_tourist_arrivals_2011" text,
  "change_2011_to_2012" text,
  "change_2010_to_2011" text
);
SELECT "international_tourist_arrivals_2011" FROM "the_americas" WHERE "international_tourist_arrivals_2012"='23.4 million';