CREATE TABLE table_3640 ("Round" FLOAT, "Date" TEXT, "Grand Prix" TEXT, "Circuit" TEXT, "MotoGP winner" TEXT, "Moto2 winner" TEXT, "125cc winner" TEXT, "Report" TEXT)

How many MotoGP winners were there when the circuit was Catalunya?
SELECT COUNT("MotoGP winner") FROM table_3640 WHERE "Circuit" = 'Catalunya'
SELECT COUNT("MotoGP winner") FROM "table_3640" WHERE "Circuit" = 'Catalunya'