Number of futures contracts bought and sold = total spot value/stock index futures contract value × β coefficient. Among them, the value of stock index futures contract = futures index point × multiplier per point. It is not difficult to see from the formula that the number of futures contracts to be bought and sold is related to the size of β coefficient when the total spot value and futures contract value are determined, and the larger the β coefficient, the more futures contracts are needed; On the contrary, the less.