CREATE TABLE table_204_691 (id DECIMAL, "date" TEXT, "round" TEXT, "opponent" TEXT, "venue" TEXT, "result" TEXT, "attendance" DECIMAL, "scorers" TEXT)

how many games had the attendance of at least 20,000 ?
SELECT COUNT(*) FROM table_204_691 WHERE "attendance" >= 20000
SELECT COUNT(*) FROM "table_204_691" WHERE "attendance" >= 20000