If the physical object is delivered on the delivery date, the futures can be regarded as the spot kept by a third party, so the price of the futures should be equal to the spot price plus the custody fee, that is,

Futures price = spot price+(monthly storage fee+monthly insurance premium+(spot price-deposit) × annualized risk-free interest rate/12)× month.

According to the actual situation, it is necessary to adjust the cost of some other delivered goods. For example, it takes more manpower and material resources for the supply and demand sides of goods to be delivered to the delivery warehouse than for direct delivery, so the futures price will be deducted from the corresponding cost.

If there is a big difference between the futures price and the above theoretical price, there will be arbitrage space, and the arbitrageurs will enter the market to balance supply and demand and return the price to the theoretical price.