When bank of America merrill lynch survey of investors results also showed that as many as 8% of the respondents expected net amount, 2018 of the yield curve will become flat, it is up to the number of records since June last year. First of all, the earnings of the fund in 2017 are in an uncertain environment. The first half of the market is in a period of "cash shortage". Towards the end of the year, the central bank started to fight for the "money shortage", so monetary policy eased and interbank money market rates fell. As a result, yu 'ebao's yields suddenly fell below the 4 per cent mark. Maintain a "buy" rating Commercial vehicles: vehicles used for transporting personnel and goods in design and technical features, and can be tractor-trailer. Passenger cars are not included. Commercial vehicles are divided into three categories: passenger cars, vans and semi-trailer tractors. The passenger bus subdivided into small passenger car, city bus, coach, tourist bus, articulated bus, coach, cross-country coach and private bus. Goods vehicles are subdivided into general goods vehicles, multi-purpose lorries, full trailer tractors, off-road trucks, special operations vehicles and special goods vehicles. 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.