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曼昆 – 经济学原理 30

Summary of Chapter 30 – Money Growth and Inflation

关键词：

quantity theory of money: 货币数量论
nominal variables: 名义可变因素
real variables: 实变量
monetary neutrality: 货币中性
velocity of money: 货币流通速度
inflation tax: 通货膨胀税
Fisher effect: 费雪效应
shoeleather costs: 皮鞋成本
menu costs: 菜单成本

In the long run, the overall level of prices adjusts to the level at which the demand for money equals the supply. The quantity theory of money asserts that the quantity of money available determines the price level, and that the growth rate in the quantity of money available determines the inflation rate.

The principle of monetary neutrality asserts that changes in the quantity of money influence nominal variables but not real variables. One application of monetary neutrality is the Fisher effect: when the inflation rate rises, the nominal interest rate rises by the same amount so that the real interest rate remains the same.

A government can pay for some of its spending simply by printing more money. When countries rely heavily on this “inflation tax“, the result is hyperinflation.

Although inflation does not influence real variables of economy and does not in itself reduce people’s real purchasing power, it does have costs:

• shoeleather costs associated with reduced money holdings;
• menu costs associated with more frequent adjustment of prices;
• increased variability of relative prices;
• unintended changes in tax liabilities due to nonindexation of the tax code;
• confusion and inconvenience resulting from a changing unit of account;
• arbitrary redistributions of wealth between debtors and creditors.

Many of these costs are large during hyperinflation, but less clear for moderate inflation.