From Earned Value to Earned Schedule - Addressing a Gap

For a while now, people have been complaining that, while Earned Value is an excellent tool for cost management, it has some gaps when it comes to managing schedules.

For example, at the end of a project, the Schedule Variance (SV) is always zero. The Schedule Performance Index (SPI) always ends up at 1.00 (perfect score). That's because at the end of a project, all of the planned work has been completed. The concept is only good earlier in the project to show how much has been completed versus what percent should have been completed at this point in time.

Enter Earned Schedule. Earned Schedule addresses this gap by adapting Earned Value metrics to duration. It's being used more frequently now, especially in the defense industry (where Earned Value began), and is already mentioned in PMI's Earned Value Practice Standard. The idea is to use Earned Value for cost reporting, and Earned Schedule for schedule reporting.

Here is a great article from the Software Technology Support Center (STSC) explaining the concepts of Earned Schedule...

STSC CrossTalk - Connecting Earned Value to the Schedule - Jun�2005