What is the sum of the stages for category 1 races after the year 2003?
CREATE TABLE "appearances_in_tour_de_france" (
  "year" real,
  "stage" real,
  "category" text,
  "start" text,
  "finish" text,
  "leader_at_the_summit" text
);
SELECT SUM("stage") FROM "appearances_in_tour_de_france" WHERE "category"='1' AND "year">2003;