动态与静态投资收益率之关系研究
2020-11-02郭春显



摘要:动态投资收益率与静态投资收益率是投资分析中重要的评价指标,对二者关系论述较少。分析发现,若项目年净收益相等,动态投资收益率一定时,静态投资收益率与投资大小无关,且与动态投资收益率关系是随项目寿命变化出现相等-最小-相等的关系,在坐标上显示为不对称的U形曲线;随动态投资收益率变动,静态投资收益率形成一系列U形曲线,U形曲线最低点连线对应投资寿命和最小静态投资收益率,贷款和投资项目年限设定不应选在此连线上。
Abstract: The dynamic return on investment and the static return on investment (ROI) are important evaluation indexes in investment analysis, but the relationship between them is seldom discussed. In this study, it is found that if the annual net return of a project is equal and the dynamic ROI is fixed, the static ROI has nothing to do with the size of the investment, and there is an equal-minimum-equal relationship between the static and the dynamic ROI with the change of the project life, which is shown as an asymmetric U-shaped curve on the coordinate. With the change of the dynamic ROI, the static ROI forms a series of U-shaped curves, and the line linking the lowest points of the curves corresponds to the investment life and the minimum static ROI, note that loan and investment project life should not be selected on this line.
关键词:静态投资收益率;内部收益率;项目评估
Key words: static return on investment;internal rate of return;project evaluation
中圖分类号:F062.4 文献标识码:A 文章编号:1006-4311(2020)29-0051-04
1 问题提出
在项目投资分析评价领域,学术界研究比较多的是动态投资收益率,也即内部收益率(IRR)指标的含义、计算、评价标准等[1],在对初始投资的收益率如何反映的研究中,认为无论是IRR,还是NAVR(净年值率),甚至ERR(外部收益率),都是从某个角度测度投资项目的项目收获率的[2]。有研究认为“修正内部收益率”应该成为最具价值的投资收益率[3]。还有研究发现内部收益率和各种修正内部收益率在评价单个项目时具有一致性[4]。对混合投资项目利用IRR评价,提出混合投资项目IRR高于外部收益率则项目通过[5]。
对动态投资收益率和静态投资收益率两者关系的讨论,是将投资分析中的等额年金(A)和初始投资(P)相除,即A/P看作投资收益率,认为当项目寿命期(n)确定时,IRR与A/P存在一个直线(IRR=k·A/P-b)线性关系[6]。那么n、IRR和A/P三者之间,IRR确定后,静态投资收益率的大小,以及与寿命n之间有什么样的关系,没有搜到研究论文。……
