What is the year when the performance is 60.73m and the age (years) is more than 45?
CREATE TABLE "new_zealand_track_field_championships" (
  "year" real,
  "place" text,
  "event" text,
  "performance" text,
  "age_years" real
);
SELECT COUNT("year") FROM "new_zealand_track_field_championships" WHERE "performance"='60.73m' AND "age_years">45;