What is the sum of the years with bus conner as the BSU head coach?
CREATE TABLE "ncaa_division_i_tournament_results" (
  "year" real,
  "round" text,
  "opponent" text,
  "result" text,
  "bsu_head_coach" text
);
SELECT SUM("year") FROM "ncaa_division_i_tournament_results" WHERE "bsu_head_coach"='bus conner';