经济周期波动是指经济运行过程中经济扩张与经济收缩的相互交替，是国民经济发展中循环出现的上下波动现象。这种周期性波动可以通过国民收入、国民生产』总值、工业生产指数等综合经济指标的变化显示出来。在一定时期内，经济运行从一个最低点升至最高点，再由最高点降至最低 Economic cycle fluctuations refer to the mutual alternation between economic expansion and economic contraction in the course of economic operation, which is a cyclical fluctuation in the national economic development. Such cyclical fluctuations can be shown by changes in the comprehensive economic indicators such as national income, gross national product, and industrial production index. In a certain period of time, the economic operation rose from its lowest point to its highest point and then from its highest point to its lowest point