Which Station users 2005–06 has a Station users 2004–05 of 2,117,300?
CREATE TABLE "stations" (
  "station" text,
  "local_authority_a" text,
  "servedby" text,
  "station_users_2004_05" real,
  "station_users_2005_06" real
);
SELECT MIN("station_users_2005_06") FROM "stations" WHERE "station_users_2004_05"='2,117,300';