The mathematical discount formula is discount = actual selling price ÷ original selling price × 100%. Discount means that when buying and selling goods, they are priced according to a certain percentage of the original price, such as 90%. This is called 10% discount or 10% discount.

There are many kinds of discounts used in international trade, including general discounts, quantity discounts for expanding sales, special discounts for special purposes and year-end rebates.

If the discount rate is stipulated in the price terms, it is called "Ming deduction"; On the contrary, it is "hidden buckle". Discount is directly related to the price of goods. Whether discounts and discount rates are included in commodity prices affects commodity prices. The higher the discount rate, the lower the price. Discount is the inevitable product of market economy. Appropriate use of discounts is conducive to mobilizing the enthusiasm of buyers and expanding sales. In international trade, it is a means to strengthen foreign competition. Folk call it a discount.