内部收益率又称内含报酬率(IRR),是企业评价投资项目时常用的方法。内部收益率是使投资项目的净现值等于零的贴现率。其计算公式为:(?)式中:NCFt 表示第 t 年的现金净流量;r 为内部收益率;n 为投资项目使用年限;C 是初始投资额。内部收益率实际上反映了投资项目的真实报酬率,目前越来越多的企业使用该项指标对投资项目进行评价。内部收益率相对其它评价指标如净现值、现值指数等而言,计算过程比较复杂。几乎所有财务管理及 Internal rate of return, also known as internal rate of return (IRR), is commonly used in corporate valuation of investment projects. Internal rate of return is the discount rate that equates the net present value of an investment project to zero. The formula is: (?) Where: NCFt said net cash flow in year t; r for internal rate of return; n for the useful life of investment projects; C is the initial investment. Internal rate of return actually reflects the true rate of return on investment projects, more and more companies use the index to evaluate investment projects. The internal rate of return relative to other evaluation indicators such as the net present value, present value index, the calculation process is more complicated. Almost all financial management and