Cost Benefit Analysis for Projects: A step by step approach

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Last updated on
16th Mar, 2021
03rd Jul, 2020
Cost Benefit Analysis for Projects: A step by step approach

Organizations, both for-profit and not-for-profit ones, often contemplate the need to take up new initiatives, develop new policies, bring about changes or create new capabilities to improve their current state of business-as-usual and create new benefits for the organization and stakeholders. 

All such new initiatives will be taken up as new projects by the organizations. These projects are expected to create new business value or in some cases social value. Every new project or initiative will require fresh investments of efforts and money to be made. Organizations will need to make such decisions prudently by creating a clear justification.  

Cost Benefit Analysis (CBA): What is it? 

Understanding Cost Benefit Analysis 

Conducting a cost benefit analysis (CBA) or a Benefit-Cost analysis (as may be referred alternatively) is one of the most fundamental methods used to compare the financial cost to be incurred for such new initiatives and benefits to be generated from them.  

Origins of Cost Benefit Analysis 

To undertake new initiatives is an integral part of the evolution of mankind, at a personal level, at a social level or at a business level. On the social front, it may involve initiatives like developing new townships, new buildings, new schools, new hospitals, new monuments, new social infrastructures, and new offices. On the business front, it may involve developing new products, new services or new production capabilities. 

There has always been a need to make sound and clear decisions. As the accountability of leaders on financial matters continues to rise, the need for doing a cost-benefit-analysis also becomes inevitable. CBA as a practice becomes part of policy matters in government projects in the US dating back in 1936, when Corps of Engineers started doing CBA for Federal Waterway Infrastructure projects. 

Approach to Cost Benefit Analysis 

A fundamental approach to do CBA includes estimating all the costs to be incurred in doing the project and carefully evaluating and estimating all the benefits to be garnered from the project. Benefits can include both quantifiable financial benefits and non-quantifiable benefits such improvement in quality of life, ease of living, ease of doing business etc. 

The purpose of Cost Benefit Analysis 

We already discussed that every new project needs investments to be made with the expectation of returns from the investments. There are two main applications of conducting a CBA: 

  1. To determine if an investment decision is sound, calculating if its benefits outweigh its costs and by how much. 
  2. To provide a basis for comparing alternative investment options, comparing the total expected cost of each option with its total expected benefits, thereby creating a basis for selecting the most desirable/viable option. 

Costs and Benefits 

Estimating costs 

Estimating all costs to be incurred in doing a project is the first important part of CBA. It will involve carefully estimating and listing the required quantity, quality and duration of material, labor, equipment and facilities to be used for completing all the activities of project work. Then we can estimate the costs for each of the above categories of resources. There will also be a need to include cost for contingency, inflation, cost of financing (if needed) and cost of any other services (such as training, liaison etc.) which may be required to complete the project activities. 

Cost estimation can be done with a considerable amount of accuracy level if all the activities of the project can be identified and all resource quantities can be estimated as stated above.  

Estimating benefits 

Estimating all benefits to be garnered is the second important part of CBA. Every project or investment done is expected to deliver benefits in future. Benefits can include financial benefits by means of increase in profit margins and increase in efficiency of doing things. Benefits can also include non-financial benefits such as increased comfort and ease of doing things, improved moral of people, increased satisfaction levels, more peace, social benefits etc. Financial benefits can be estimated with considerable amount of accuracy, while it will be somewhat challenging to estimate and quantify the non-financial benefits. 

Comparing costs and benefits 

After careful and diligent estimation of costs and benefits as stated above, we need to compare the costs to be incurred with benefits to be garnered. If the benefits outweigh the costs considerably, such proposals will be taken up for further consideration by the organizations. Organizations may lay down clear guidelines regarding minimum expected difference between benefits to cost for the projects to be selected for implementation. Organizations may also lay down clear guidelines for evaluating the social benefits (mostly non-financial as explained above) for clear decision-making after doing a CBA. 

How to do a Cost Benefit Analysis  

To conduct cost benefit analysis, we need to estimate and enumerate all costs to be incurred and all benefits to be generated. Then one needs to compare the costs with benefits for arriving at suitable decisions and recommendation about whether the project is worthy of taking up or not. 

There are two broad methods for doing cost benefit analysis: 

  1. Non-discounted method (does not consider the effects of interest and time period). 
  2. Discounted method (considers the time period, interest, inflation etc. while calculating the costs and benefits) 

We can take a simple example below to illustrate some of these methods.  

Analyzing using non-discounted method 

These are very simple methods without considering the effects of interest and time period.The below illustration shows the costs incurred and benefits over a period of six years.  

Yr. 0Yr. 1Yr. 2Yr. 3Yr. 4Yr. 5Yr. 6Discount rate at 10% (0.1)

Example of CBA using Non-Discounted Method

Total Cost = 100000; Total Benefits = 150000 

  • Benefit Cost Ration (BCR) = Total Benefits / Total Costs = 150000/100000 = 1.5 (> than 1) 
  • Profit = Total Benefits (Revenue) – Total Costs = 150000 – 100000 = 50000 
  • Payback Period = Time taken to recover the total cost (investments) = 4 years 
  • ROI = Return on Investment = Profit/Investment = 50000/100000 = 50%  

Using the above simple non-discounted methods we can see that this project looks good with benefits being more than the cost, with positive profits and lower payback period.  

But these calculations are too simplistic, and do not account for the time-value of money based on interest rates, inflation. 

Analyzing using discounted method 

In the above example, the costs are incurred in the present time, while the benefits will be received in future. These values of money are in different timelines and hence their values cannot be compared directly as it is. We need to bring down all the future values of benefits and costs to their corresponding present values and then we can do a comparison of present values of benefits and costs. 

The below formula can be used to understand the relationship between present value (PV) and future value (FV) of money. 

  • PV = FV/(1+r)n(where r stands for rate of discount of money, n stands for time period) 

In the below example, the cost and benefits value mentioned are in specific period in time. We need to bring all costs as well as all benefits to their corresponding present values (PV) using the above equation and assuming an interest (discount) rate of 10% for ease of calculation.   

Yr. 0Yr. 1Yr. 2Yr. 3Yr. 4Yr. 5Yr. 6Discount rate at 10% (0.1)
Cost (FV)100000000000
Cost (PV100000000000

Example of CBA using Discounted Method

  • PV of all costs = 100000 (as it is happening in year 0 only) 
  • PV of all revenue = 25000/(1.1) + 25000/(1.1)2 + 25000/(1.1)3+ 25000/(1.1)4+ 25000/(1.1)5 +  25000/(1.1)6 = 22727+20661+18782+17075+15527+14112 =108884 
  • Net Present Value (NPV) = Sum of PV of all benefits – Sum of PV of all costs = 108884 – 100000 = 8884 (> 0)  

Hence this project investment will lead to a profit after discounting the effect of interest and any other inflationary factors which are taken as 10%) 

If NPV is > 0, then the project investments will lead to profit. NPV is one of the most practical methods for doing cost benefit analysis by considering the time-value of money.  

  • IRR (Internal Rate of Return) – IRR is the rate of discount at which the sums of PV of all benefits equals sums of PV of all costs. Or in other words IRR is the rate of discount at which NPV equals 0.  Calculating IRR is a more complex affair. In simpler term IRR denotes expected rate of return from the investments. According to a general guideline, higher the IRR from an investment, the better the opportunity.  

How to establish a framework 

As we discussed above, there are various methods for undertaking cost benefit analysis. Different financial parameters such as Benefit Cost Ratio (BCR), ROI, Payback Period, NPV, IRR etc. need to be calculated for arriving at decisions and making necessary recommendations on whether a specific project should be taken up or not. 

Every organization is unique in their capabilities to invest and take risk. Organizations can define their specific guidelines or framework for project selection taking into account the above financial parameters, the risks involved in doing the project and most importantly specific nature of the investors. A framework for project selection will include all above factors.  

Below are some basic guidelines which are used for decision making during cost benefit analysis (CBA) 

  1. NPV should more than 0. Higher the NPV, the better is the project. 
  2. BCR should be more than 1. Higher the BCR, the benefits outweigh the cost more. 
  3. ROI should be high. Higher the ROI, the better is the investment opportunity. 
  4. IRR should be high. Higher the IRR, the better is the opportunity. 
  5. Payback period should be lower. Lower the payback period, the better seems the opportunity. 

Challenges and considerations while doing CBA 

How accurate is Cost Benefit Analysis? 

Cost benefit analysis can be reasonably accurate if these are done by technical and financial experts. Experience and availability of real data about costs and benefits of similar projects from past can greatly enhance the accuracy of cost benefit analysis.  

Are there limitations to Cost Benefit Analysis? 

Since cost benefit analysis requires estimating costs and quantifying future benefits accurately, it requires solid maturity in terms of knowledge and availability of past data. In the absence of experience and data availability, CBA may fall short in its accuracy.  

The risks and uncertainties in Cost Benefit Analysis 

While doing cost and benefit analysis, it will be important to understand risks and uncertainties involved in doing the project. It will also be equally important to understand the uncertainties involved in realizing the benefits once the project is done. Cost benefits analysis need to consider the implications of uncertainties to make it realistic. It may require doing statistical simulations and modeling as well.  

Cost Benefit Analysis in the real world 

We saw that CBA became a formal and mandatory practice as early as 1930s in the US government departments, for numerically evaluating if the benefits will outweigh (and by how much) the costs of doing the project.  

Organizations have become highly knowledgeable, experienced, and matured. Availability of past data coupled with ability to process the data using modern mathematical and statistical techniques and computerized tools exists in abundance within organizations.  

In today’s world the need for doing CBA has become necessary. Businesses and governments are held more and more responsible and accountable to their citizens and investors for justifying their investment decisions. They can do this only by conducting a thorough cost benefit analysis.  



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