CREATE TABLE table_204_641 (id NUMBER, "pos" CLOB, "no" NUMBER, "driver" CLOB, "constructor" CLOB, "laps" NUMBER, "time/retired" CLOB, "grid" NUMBER, "points" NUMBER)

what is the number of drivers who did n't finish the race due to engine trouble ?
SELECT COUNT("driver") FROM table_204_641 WHERE "time/retired" = 'engine'
SELECT COUNT("driver") FROM "table_204_641" WHERE "time/retired" = 'engine'