CREATE TABLE table_203_598 (id DECIMAL, "date" TEXT, "time" TEXT, "opponent" TEXT, "site" TEXT, "tv" TEXT, "result" TEXT, "attendance" DECIMAL)

which game date only had 31,840 people in attendance ?
SELECT "date" FROM table_203_598 WHERE "attendance" = 31840
SELECT "date" FROM "table_203_598" WHERE "attendance" = 31840