CREATE TABLE table_16437 ("Pilot car No." FLOAT, "Colour" TEXT, "Serial No." TEXT, "Engine No." FLOAT, "Registration No." TEXT)

What is the number of colour with the regisration number of mg-509?
SELECT COUNT("Colour") FROM table_16437 WHERE "Registration No." = 'MG-509'
SELECT COUNT("Colour") FROM "table_16437" WHERE "Registration No." = 'MG-509'