How do you handle new tasks in an earned value analysis chart?

Question

Earned Value Analysis is great on paper. However, I'm having difficulty using it for programming projects that tend to change dramatically from week to week.

For example, a milestone is "complete test plan 2 on accounting package", however, in the first half hour of the test plan, the tester discovered an unrecoverable bug. Fixing the bug is 3+ weeks worth of work that was never in the work break down structure. The programmer says, "oh yeah I forgot to include that task" when we made the task list.

So, how do you handle this? Do you create the chart so that your project is now a month behind schedule and a month over cost because the WBS was incomplete? Hard to swallow when the entire project is 6 weeks long. Or, do you adjust the planned value to include this new 3 weeks worth of work thus creating a new project plan?

To further extend the question, how do you handle disagreements about the meaning of a work item. The programmer says it's done. The stake holder explains why the three legged cat is missing a leg and the programmer says, oooh you wanted 4 legs?? Well, that's going to take an additional 3 weeks. The new cat will have more value with the extra leg... but the project will take 3 weeks longer than estimated. How do you handle this?

Answer 1

That is called a variance. It is not a missing task. It is work in scope but not planned. This means you cannot claim EV on that package until the extra effort is finished.

You will accrue an unfavorable SV and CV.

The four legs example is iffy. If you had explicit requirements about the three legs, then you have a change. Add it and strike a new baseline. If not, you have an issue. Likely, you will have extra effort and more bad variances.

Answer 2

David is correct, you simply have variances that will be unfavorable.

Here's part of the problem as I see - you're trying to use EV, which assumes (and requires) an accurate level of detail in work package breakdown, and an understanding and agreement on what 'done' looks like. As long as you have situations where you're arguing about three-legged cats, EV will be worthless as it will ALWAYS be unfavorable due to that addition of new tasks.