Network planning technology was developed and developed in the United States in the late 1950s. This approach includes a variety of web-based methods, such as critical path method, planning review technology, combined network method, etc. On the other hand, if investors think that inflation will worsen or worsen, interest rates may rise to curb inflation, and bond prices will fall. First half of the 1980 s, the United States there is a lot of huge budget deficit and trade deficit, the dollar remains strong, is the United States adopted a policy of high interest rates, which makes a lot of capital from Japan and Western Europe into the results of the United States. The trend of the dollar has been greatly influenced by interest rate factors. Interest rate decision theory The capitalist mode of production first developed from industry and gained dominance, then gradually expanded to agriculture. Because there are two kinds of monopoly in the agriculture, the monopoly capitalism and operation of land and land ownership of monopoly, so it does not have such as like the sort of free competition in the industry, thus hindering the average profit margin. Therefore, the excess profit in agriculture is converted into rent. First, the individual production price of land products is lower than the social production price. The second is absolute rent from the value of land products beyond the price of social production. Both rent entity, agricultural employment is part of the surplus value created by laborer, it embodies the land owners through agricultural capitalist production relations of common exploitation agricultural workers. On the surface, however, the rent is distorted as the value of the land itself, or the gift of nature, thus disguising the real class relationship completely. Accounting earnings include only realized gains, and exclude unrealized gains and losses, the economic benefits will be enterprise's operating earnings and are favorable to the same treatment, regardless of whether they have been implemented. Thus, in general, accounting gains are less than economic gains, and the difference is mainly in the interest.