Any transaction can be seen as a contract between the two parties. The so-called transaction cost can be seen as the cost of the transaction contract. According to Mr Coase and others, a type of transaction costs arise from the accidental factors that occur when a deal is signed. These incidental factors may not be written into the contract due to the fact that they could not be foreseen in advance, or although they could be foreseen, they could not be written into the contract due to too many factors. Another type of transaction costs is the signing of contracts and the cost of monitoring and enforcing contracts. Mehrotra said the additional rate for PC flash drives in 2017 is about 35 percent, and will increase to 75 percent by 2020. And "a lot of hard drives still need to be replaced by SSDS... Future self-driving vehicles are expected to be equipped with about 40GB of DRAM... This will also drive the use of NAND flash memory." The market is the condition that Commodity Exchange is carried out smoothly, it is commodity circulation domain all Commodity Exchange activity total. The market system is made up of all kinds of professional market, such as goods and services market, financial market, labor market, technology market, information market, the real estate market, cultural market, a complete system of tourism market, etc. At the same time, each professional market in the market system has its special functions, which are interdependent and mutually restricted, and work together in the social economy. The international monetary fund has strongly defended its gloomy forecast of the UK after brexit, saying a warning of a slowdown in growth is imminent. Read more