Concept: Earned Schedule is the time on a project at which the value currently earned should have been earned. See Chart 1 and Lipke (2003). To calculate the amount of Earned Schedule, compare the Earned Value (BCWP) at the current time to the Planned Value (BCWS) at the end of each time period in the schedule. Count the number of time periods in which the Earned Value is greater than or equal to the Planned Value. Add in any fractional amount.*
Chart 1
Practice: The Earned Schedule metric (ES) is the basis for an array of associated metrics (SPIt, EACt, TSPI, P Factor, and others). Beyond that, ES is a useful measure in its own right. Here’s how to apply it in practice.
Assuming a wellformed plan, the value earned on a project is expected to track the value planned for the project. That is, for each time period spent, an equivalent amount of time should be earned.
Earned Schedule quantifies how much time is actually earned for the time spent. When compared to the expected track, the ES metric shows how well or poorly time is being used relative to the expected utilization.
To borrow a practice from the Agile framework, we can depict the utilization using a Burndown Chart. See Saddington (2013). Let’s call our version the Schedule Burndown. (See Chart 2.)
Chart 2
In the Schedule Burndown Chart, the vertical scale represents the total number of periods remaining in the project. The horizontal scale represents the end date of each period.
The Expected Burndown line represents the expected track for time utilization, running straight from the first period to the last planned period. The ES Burndown line shows how much time has actually been earned, extending from the first period to the last scheduled period. To get the ES Burndown, you decrement the planned total by the amount of schedule that is earned in each period.
If the ES Burndown line is above the Expected Burndown line, the project is late. If the ES Burndown line is below the Expected Burndown line, the project is early.
If the project is late, the total number of periods will grow greater than the number of planned periods. Hence, in Chart 2, both Burndown lines start at period 8, rather than period 10. To finish, two periods were added to the schedule beyond the ones in the baseline.
Similarly, the Expected Burndown line finished two periods before the end, reflecting the fact that it took 10 periods to earn 8 periods.
The ES Burndown Chart is easy to create and to understand. It is especially useful as a communication tool and as a firststep in your Earned Schedule practice.
Notes *To find the fractional amount, divide the amount of value earned in the fractional period alone by the total amount of value planned for the same period.
References Lipke, W. (2003). Schedule is Different. The Measurable News, Summer. Saddington, P. (2013). The Agile Pocket Guide. Hoboken, New Jersey: Wiley.
