When the price of raw materials increases or decreases, the production coats increase or decrease. Second, the price of substitute products also affects the supply curve. Because relative products are competitive relationships, when the price of one product rises, another falls. This will affect supply. Third, production technology will affect the supply curve. As the level of technology increases or decreases, production costs decrease or increase. finally, government policies will affect the supply curve. Positive policies will increase supply, conversely, it will decrease. For example, if the government limits the number of cars people can buy, this will cause the supply curve to shift. In addition, the future price of the product and the development of the product business will also affect the supply.