In this way, if the interest rate of a country is higher than that of other countries, it will attract a large amount of capital inflow, and the outflow of funds from the country will decrease, leading to the buying of this currency in the international market. At the same time, the capital account balance has been improved, and the currency exchange rate has been raised. On the other hand, if a country is loose credit, interest rates fell, if interest rates lower than in other countries, can cause large capital outflows, foreign capital inflows to reduce, the capital account balance of payments deteriorates, while selling the currency in foreign exchange market, caused the exchange rate to fall. Read more In the 1920s and 1930s, the great depression forced western economic theorists to reflect on the definition of the market. The final answer is completely laissez faire is not enough, the invisible hand sometimes does not exist, market failure, government should be on economic activity on the "total" intervention, so "macroeconomics" was born. Roosevelt also accepted Keynes's proposal to impose a "New Deal" on government intervention in the economy. It has now formed the world's most consensus-building government: fiscal policy, monetary policy, and, of course, none of these "new" policies. The division of labor is becoming more and more elaborate, the process is more and more complicated, and the coordination is more strict. To put these complex organisms organized scientifically, make each link and department activities can join each other in time, space and Numbers, both around the overall objectives, and acted, coordinate each other, there must be a strict plan. The organization, coordination, control and so on in management, if there is no plan, is as unthinkable as the automobile assembly plant without the design of the process.