When a futures contract expires, like other futures, it needs to be delivered. However, general commodity futures, treasury bonds futures and foreign exchange futures are delivered in kind, while stock index futures and short-term interest rate futures are delivered in cash. The so-called cash delivery means that there is no need to deliver a basket of stock index components, but the spot index on the maturity date or the next day is used as the final settlement price, and the position is closed through profit and loss settlement at the final settlement price.