What are the changes (2010 to 2011) where the International Tourist Arrivals is 1.7 million?
CREATE TABLE "africa" (
  "rank" real,
  "country" text,
  "international_tourist_arrivals_2011" text,
  "international_tourist_arrivals_2010" text,
  "change_2010_to_2011" text,
  "change_2009_to_2010" text
);
SELECT "change_2010_to_2011" FROM "africa" WHERE "international_tourist_arrivals_2011"='1.7 million';