As the center of global automotive engine research and development and production, Britain's powertrain design has always maintained the world's leading level, especially in engine design. In 2013, the UK produced 2.55 million engines, accounting for 30 per cent of total European engine production, with 62 per cent of the engines exported to more than 100 countries. In finance, investing means buying securities or other financial or paper assets. Valuation is a way to estimate the price of a potential investment. The types of investments include real estate, securities investment, gold, foreign currency, insurance or bonds or stamps. These investments may then provide future cash flows that may increase or decrease their value. The investment in the stock market is carried out by securities investors. Interest rate, in the form of expression, refers to the ratio of the amount of interest to the total amount of borrowed capital in a certain period of time. [1] the interest rate is the interest level per unit time of the unit currency, indicating the interest rate. Economists have been looking for a theory that can fully explain the structure and change of interest rates. Interest rates are usually controlled by the central bank of the country and administered by the federal reserve board in the United States. Today, interest rates are one of the important tools for macroeconomic regulation. Generally speaking, the interest rate varies according to the term of measurement, indicating that the method has annual interest rate, monthly interest rate and daily interest rate. Abn amro believes that after a strong 2017, precious metals will face many headwinds at the start of 2018. The bank said rising dollar and bond yields would put downward pressure on gold and silver prices in 2018. Gold is expected to trade between $1,200 / $1,250 an ounce next year. His European central bank held interest rates unchanged and signaled that it would maintain its aggressive currency, despite data showing strong economic performance in the region. In his theory, money supply is controlled by the central bank and is an exogenous variable with no interest rate elasticity. At this point, monetary demand depends on people's psychological "liquidity preference".