CREATE TABLE table_16577 ("#" FLOAT, "Episode" CLOB, "Rating" CLOB, "Share" FLOAT, "Rating/Share  ( 18-49 ) " CLOB, "Viewers  ( millions ) " CLOB, "Rank  ( timeslot ) " FLOAT, "Rank  ( night ) " FLOAT, "Rank  ( week ) " CLOB)

How many viewers (millions) were there for rank (week) 20?
SELECT COUNT("Viewers (millions)") FROM table_16577 WHERE "Rank (week)" = '20'
SELECT COUNT("Viewers (millions)") FROM "table_16577" WHERE "Rank (week)" = '20'