What is the number of jurisdiction for 57.3 percent?
CREATE TABLE "results_of_the_national_referendum_on_pr" (
  "jurisdiction" text,
  "for_prohibition" real,
  "percent_for" text,
  "against_prohibition" real,
  "percent_against" text
);
SELECT COUNT("jurisdiction") FROM "results_of_the_national_referendum_on_pr" WHERE "percent_for"='57.3';