How many years had scores of 10–12, 6–1, 6–3?
CREATE TABLE "mixed_doubles_8_3_titles_5_runner_ups" (
  "outcome" text,
  "year" real,
  "championship" text,
  "surface" text,
  "partner" text,
  "opponents" text,
  "score" text
);
SELECT COUNT("year") FROM "mixed_doubles_8_3_titles_5_runner_ups" WHERE "score"='10–12, 6–1, 6–3';