how many vehicles where top 13 time is 1:18.72
CREATE TABLE "2008_taupo_1_november" (
  "pos" real,
  "driver" text,
  "vehicle" text,
  "top_13_time" text,
  "shoot_out_time" text,
  "best_time_of_day" text
);
SELECT COUNT("vehicle") FROM "2008_taupo_1_november" WHERE "top_13_time"='1:18.72';