accounting profit and loss statement Marx's interest rate determinism is based on the source and essence of interest. Marx reveals that interest is a portion of the surplus that the capitalist who lends capital is divided from the capitalist who borrows the capital, and the profit is the transformation form of the surplus value. Full market competition will make economic activity full of vigor and vitality. Jeffrey Currie of Goldman sachs analyst and Michael Hinds, wrote in the latest report, the next three months, six months and 12 months of gold prices were at $1225 an ounce and $1200 an ounce and $1225 an ounce. Two extremes can be envisaged. In an extreme case, each production is done by a single individual, such as a person making a car. In this way, the person is going to trade with a lot of intermediate goods suppliers, and also to trade with the demanders of their products. In this case, all transactions are conducted through the market in many individuals. In another extreme cases, all the production in the economy in a large enterprise, such as the complete car was produced in the enterprise interior, don't need to make any intermediate products trading market. Therefore, the same transaction can be conducted either through the organizational form of the market or through the organizational form of the enterprise. Companies exist, or companies and markets coexist, because some transactions cost less in the enterprise, while others cost less in the market.