CREATE TABLE table_31178 ("Athlete" CLOB, "Event" CLOB, "Elimination Poule" CLOB, "Round of 16" CLOB, "Quarterfinals" CLOB, "Semifinals" CLOB, "Final" CLOB)

How many athletes were named federico muller?
SELECT COUNT("Quarterfinals") FROM table_31178 WHERE "Athlete" = 'Federico Muller'
SELECT COUNT("Quarterfinals") FROM "table_31178" WHERE "Athlete" = 'Federico Muller'