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Earned Value Management (A Case Study)
By Tom Carlos (PMP) – Project Perfect

Overview

There are “lucky” project managers whose projects were completed “on time” and “within budget.” But I am guessing they are in the minority. Everyone else has probably faced a situation where one of the following statements is true:

  • The project is within budget and schedule but we do not see the “expected” results
  • The project is taking longer than expected
  • The project is costing more than anticipated

I am betting that the managers of these projects used analysis tools that are considered “two-dimensional.” “Budget” and “Actual” are the two dimensions. But in looking at a broader picture, there is a much needed third dimension- one that reflects “performance and efficiency.”

“Performance and efficiency” indicate whether or not we are actually completing the intended tasks and producing the expected project deliverables within the designated budget and schedule. To examine this concept, let’s look at the following case study.

Case Study

The Assumptions:

  • John is managing a software development project.
  • The project estimates include a total of 100 hours of development time.
  • There are five separate tasks that will take 20 hours each.
  • Each task has 4 subtasks that take 5 hours to complete.
  • John hires five programmers. Each will each have twenty percent of the work that can be completed concurrently.
  • Each programmer will charge $100 per hour. Total budget for the project is $10,000.
  • Based on the distribution of work, it is determined that the project can be completed within one week.

Initial Reports

  • At the end of the week, the programmers turn in time sheets.
  • A total of 90 hours is reported.
  • Based on this information, John quickly assumes the project is 90% complete.
  • John realizes that the project will not be completed on time.
  • John’s status report claims that the project is within budget but not on time.

Question for you

Would you agree with John’s assessment of the project?

If you answered “No” or “I do not have enough information to support that claim” you’re right on track. And to understand why that is the correct answer, let’s dig further into the problem.

What do we Know (for a fact)?

  • The project has 5 tasks, 20 hours each, total 100 hours.
  • The programmers were given 1 week to complete their tasks.
  • Timesheets show 90 hours of work.

What do we Not Know (to be true)?

  • How many of the tasks (or portions of a task) have been completed?
  • Do we know that work performed was solely dedicated to completing tasks or was the time spent on non-related tasks or inefficiencies?

To answer this question, John calls each programmer and gathers the following information:

Programmer Budgeted Time Actual time spent Invoices Submitted Percentage of all tasks completed
Bob 20 hours 15 hours $1,500 60%
Sue 25 hours 25 hours $2,500 75%
Roger 20 hours 5 hours $500 10%
Mike 20 hours 30 hours $3000 50%
Jill 20 hours 15 hours $1,500 80%
Total time and costs incurred 90 hours $9,500

(Table 1)

Without going any further John can see the project has encountered a serious problem. Collectively, the programmers show 90 hours of work. However, no one programmer can make the claim that they have completed 90% of their assigned task (and final deliverable).

John scratches his head and is dumbfounded when it comes to understanding

  1. What has happened and
  2. What to do next.

So he asks an associate for help and she comes to the rescue.

Margie introduces John to a project management tool called Earned Value Management (EVM). In fact, she gives him an article that has the following definition:

Earned Value Management – The process of considering scope, schedule, and resources, measured against a project’s actual performance. It compares the planned amount of work to the completed tasks, to the projects’ cost, to determine if the cost, schedule, and work completed (thus far) are all in sync and in accordance with the plan. This analysis will show past performance and will estimate future efforts to complete the project (with the desired results).

The article provided by Margie also contains a table that shows all the terms, definitions, and formulas needed to conduct EVM analysis.

At this point, John feels overwhelmed and has no idea how to apply the EVM terms and formulas to his project. So with Margie’s help, they slowly begin the analysis by defining the terms and plugging in the known figures.

Step 1 – The Starting Point Calculations

Symbol Description Formula Explanation
PV Planned Value None The estimated value of the work planned to be done thus far. In this case, the project’s PV is the estimated cost of $10,000 because we estimated the project would be completed within a week.
AC Actual Costs None The total costs incurred to date, based on timesheets, invoices, other expenses, etc. In this case $9,000
EV Earned Value Sum of all (Task Budget * % Completed) The estimated value of (intended) work completed thus far, as it relates to the expected deliverables.

(Table 2)

PV (Planned Value) and AC (Actual Cost) are easily derived. PV is based on what should have been completed thus far. For multi-period projects, it will seldom equal the full budget figure. The idea is to calculate a figure that represents “the amount of intended work; the work performed (thus far) in relationship to the assigned tasks.” In reality, EVM analysis will be done over several periods and the value for PV will be constantly changing.

To derive EV, multiply the budget figure by the percentage of all tasks completed (see Table 1). For example, Bob was given 20 hours to complete 4 subtasks. He estimated that 60% of the subtasks are completed. You multiply $2,000 by 60% and this gives a value of $1,200. So you can clearly see that Bob’s (real) work does not equal the actual cost of $1,500. As a result, Bob has fallen behind (in schedule and cost) based on this one calculation.

To calculate EV for the entire project, simply add the individual EV values for each programmer. Refer to Table 3.

Term Value Notes
PV $10,000 Our budgeted figure
AC $9,000 Total invoices submitted thus far
EV $5,500 ($2,000 * 60%) + ($2,000 * 75%) + ($2,000 * 10%) + ($2,000 * 50%) + ($2,000 * 80%)

(Table 3)

Again, we can see that the group as a whole has fallen behind on their work. They have submitted $9,000 as the cost but produced only $5,500 of (Earned) value. So at this point in time, the project appears to be $3,500 over budget. And we also know the project is behind schedule (because the tasks were not completed within the 1 week time frame).

Step 2 – The Performance Index Calculations

The Performance Index figures help us quantify efficiency. They are also used in subsequent EVM calculations.

Symbol Description Formula Explanation
CPI Cost Performance Index EV/AC I am (only) getting (blank) cents performance out of every $1 spent.
SPI Schedule Performance Index EV/PV I am only progressing at (blank) % of the rate originally planned.

(Table 4)

By plugging in our known values for PV, AC, and EV, we can calculate CPI and SPI.

Term Value Notes
CPI 61.11% Using (EV/AC); ($5,500 / $9,000)
SPI 55.0 % Using (EV/PV); ($5,500 / $10,000)

(Table 5)

Based on these results, John can see that his team is working at an average of 61.11% performance efficiency. The 55% SPI index tells him that the project will most likely need another week for completion.

Step 3 – The Final Cost Estimates

John then asks Margie; “Based on this information can we calculate the project’s final cost?” So Margie rolls out the next set of terms and calculations.

Symbol Description Formula Explanation
BAC Budget At Completion None The original budget for the total job
EAC Estimate At Completion BAC/CPI The amount “currently expected” for the total project cost
ETC Estimate To Complete EAC-AC From this point on, how much MORE do you expect the cost will be to finish the job
VAC Variance At Completion BAC-EAC How much over or under budget will the project come in at
CV Cost Variance (in dollars) EV-AC Negative is over budget, Positive is under budget
SV Schedule Variance (in dollars) EV-PV Negative is behind schedule, Positive is ahead of schedule

(Table 6)

BAC is the original budget total. For this project, it is $10,000.

Calculating a value for EAC can be tricky. There are four different methods for calculating EAC. Each method can yield a different result. Since Bob employs the principle of “conservatism” and wants the “worst case scenario” he uses the formula the yields the highest figure.

ETC is an easy calculation. This figure represents the additional costs from this point forward in order to finish the project.

Term Value Notes
BAC $10,000 The original budget
EAC $16,363 Using (BAC/CPI); [$10,000/.611]
ETC $7,363 Using (EAC-AC); ($16,363 – $9,000)
VAC – $6,363 Using (BAC-EAC); ($10,000 – $16,363)
CV – $3,500 Using (EV-AC) with answer in dollars; $5,500 – $9,000
SV – $4,500 Using (EV-PV) with answer in dollars; ($5500 – $10,000)

(Table 7)

At this point in time, the project appears to be $6,363 over budget (VAC). It will be next to impossible to hit the original target figure of $10,000. The current EAC value assumes that the programmers will continue working at the same pace.

The Cost (CV) and Schedule (SV) variances indicate that the project is “over budget” and “behind schedule.”

Step 4 – Overall Efficiency Ratings

John is shaking his head in disbelief. Not only is his project struggling to meet the original estimates, but he must now report the bad news at the next steering committee meeting. He knows that the management team will not be able to follow the calculations shown above. So he needs to simplify the reporting to three simply values.

Symbol Description Formula Explanation
PE Planned Earned EV/BAC Project % Complete (as it relates to time and deliverables)
PS Percent Spent AC/BAC Project % Spent (as it relates to cost)
CSI Cost Schedule Index CPI * SPI The overall efficiency rating. The further CSI is from 1.0, the project will have difficulties in recovering.

(Table 8 )

Using the known values, John calculates PE, PS, and CSI.

Term Value Notes
PE 55% Using (EV/BAC); ($5,500 / $10,000)
PS 90% Using (AC/BAC); ($9,000 / $10,000)
CSI .336 Using (CPI * SPI)

(Table 9)

The values for PE and PS do not surprise John. He has seen these figures before. But CSI is surprising. This value is far from “1” and indicates the seriousness of the project’s inefficiency.

The formulas provide a mathematical analysis of performance. Unfortunately, they cannot explain “why” the inefficiencies have occurred. For this, John will need to examine the work of each programmer in order to understand why they are all running over the allotted time for each task. Hopefully, he can correct the problems.

The other issue to consider is that the task lengths were severely underestimated. Interviews with the programmers may show that they in fact are working to the best of their ability. The problem may have occurred in the original project estimates.

Conclusion

There is much more to EVM than discussed in this article. But you are now aware of the third dimension of a project’s financial analysis. All three dimensions are key elements that must be considered when analyzing project performance.

Tom Carlos has over 20 years of cumulative experience in business, technical, and training environments. He is a Certified Project Management Professional (PMP) and member of the Sacramento Valley PMI Chapter. For other articles on similar subjects, you can visit www.carlosconsulting.com or contact him at tom@carlosconsulting.com.

Project Perfect is a project management software and project infrastructure consulting organisation based in Sydney Australia. Their focus is to provide creative yet pragmatic solutions to Project Management issues as well as to set up the infrastructure an organisation requires to successfully manage projects.

Project Perfect sell “Project Administrator” software, which is a tool to assist organisations better manage project risks, issues, budgets, scope, documentation planning and scheduling. They also created a technique for gathering requirements called “Method H”, and sell software to support the technique. For more information on Project tools or Project Management visit www.projectperfect.com.au

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