如所周知．经营杠杆描述的是企业存在固定成本时的利润变动率大于业务量变动率的现象。它是度量经营风险的有效工具．也是进行利润预测的基本方法。用公式可表示为：经营杠杆率利润变动率（DOL）销售变动车其中：P为基期利润；S为基期的销售量或销售额；△P为利润变动额；△S为 As we all know. The operating leverage describes the phenomenon that the rate of change of profit when the firm has a fixed cost is greater than the rate of change of the volume of business. It is an effective tool to measure business risk. It is also the basic method of making a profit forecast. Using the formula can be expressed as: Operating leverage rate of profit margin of change (DOL) sales of change vehicles where: P for the base period profit; S for the base period of sales or sales; △ P for the profit changes; △ S