An open market enables enterprises to compete and cooperate with each other on a larger scale and at a higher level to promote economic development. Suppose a speculator decides to enter the foreign exchange futures market. He is going to take out $10,000 to speculate. He selected the broker bank and registered representative, opened an account, and deposited the money. To be on the safe side, he decided to do sterling business first and then gain some experience before entering other markets. The accounting income follows the historical cost principle and the matching principle, which is conducive to the objective reflection of the business management responsibility of the enterprise management authorities. But, due to the historical cost principle inherent defects, especially according to the present value of revenue and expenses by historical cost line, makes the calculation of accounting earnings lack of inner logical unity, and the matching principle is difficult to carry out, so that the book value of assets can not reflect its real value, cost cannot be fully compensated. And the economic benefit is measured in the current value, which reflects the actual value of the asset, which is beneficial to the full compensation of the cost.