Earned Schedule (ES)

What is Earned Schedule (ES)?

Earned Schedule (ES) is an extension of the traditional project management tool known as Earned Value Management (EVM). While EVM provides quantitative data on project performance in terms of budget and cost, Earned Schedule adds a time dimension to this analysis, allowing project managers to assess the time performance of projects more accurately. Earned Schedule addresses some of the limitations of EVM related to schedule performance and forecasting, offering a more precise method for determining if a project is ahead, on, or behind schedule.

Principles of Earned Schedule

Earned Schedule is based on the same data used in Earned Value Management, including:

  • Planned Value (PV): The budgeted amount for work planned to be done by a specified time.
  • Earned Value (EV): The budgeted amount for work actually completed by a specified time.
  • Actual Cost (AC): The actual amount spent on the work completed by a specified time.

Earned Schedule takes these traditional EVM metrics and enhances them by focusing on the time aspect, specifically:

  • Scheduled Time of EV (STE): The point in time when the earned value (work performed) was originally planned to occur.
  • Actual Time (AT): The current point in time when the measurement is taken.
  • Earned Schedule (ES): A measure of the time value of work accomplished, which translates the EV into the amount of the planned schedule that should have been completed.

The fundamental addition by ES is the translation of these monetary metrics into time metrics, calculating how long it should have taken to achieve the current level of EV and comparing it to the actual time elapsed.

How Earned Schedule Works

To calculate Earned Schedule:

  • Determine Time Periods: Break down the project timeline into discrete time periods (e.g., weeks, months).
  • Calculate Earned Value (EV): Measure the budgeted cost of work actually performed up to a current time point.
  • Find the Earned Schedule (ES): Identify at what point on the project schedule the current EV should have been earned. This is done by finding the time at which the cumulative Planned Value equals the current Earned Value.
  • Assess Performance: Compare the Earned Schedule (ES) to the Actual Time (AT) to determine if the project is ahead of schedule (ES > AT), on schedule (ES = AT), or behind schedule (ES < AT).

Benefits of Earned Schedule

  • Improved Accuracy: Provides a more accurate and realistic measure of schedule performance compared to traditional methods that might show misleading recoveries late in the project.
  • Enhanced Forecasting: Allows for more reliable forecasting of project completion dates based on current performance trends.
  • Integrated Analysis: Integrates cost and schedule performance into a single comprehensive view, enhancing decision-making capabilities.
  • Proactive Management: Helps identify potential delays earlier in the project lifecycle, allowing for timely corrective actions.

Challenges and Considerations

  • Complexity: Incorporating Earned Schedule into project management processes can add complexity, requiring training and understanding from project teams.
  • Data Integrity: Relies heavily on the quality and accuracy of baseline schedule and cost data; inaccuracies in baseline data can lead to misleading ES outcomes.
  • Integration with Tools: Not all project management software supports Earned Schedule natively, which may require manual calculations or customizations.

Examples of Use

  • Construction Projects: In construction, where delays can have cascading effects on costs and project completion, ES helps in pinpointing where delays are occurring and forecasting their impacts.
  • Software Development: In agile or phased software development projects, ES can help in tracking whether the development is keeping pace with planned schedules, despite iterative changes.


Earned Schedule is a valuable tool for project managers seeking to gain deeper insights into both the cost and time aspects of project performance. By extending the traditional Earned Value Management approach, Earned Schedule provides a more detailed picture of where a project truly stands in terms of its timeline, facilitating better-informed decisions and more accurate forecasts. As with any advanced project management tool, its effectiveness is heavily dependent on the user's expertise and the accuracy of the project data.

See Also

Earned Schedule (ES) is an extension of the traditional Earned Value Management (EVM) system that incorporates time analysis into the project management tracking and forecasting process. While EVM focuses on cost performance, Earned Schedule provides a more accurate measure of time performance by translating the earned value data into a time-based schedule performance metric. This approach helps project managers understand not only how much of the budget has been spent but also how far ahead or behind schedule a project is.

  • Earned Value Management (EVM): Explaining the foundational system from which ES is derived.
  • Project Scheduling: Discussing methods and tools used in planning and managing project schedules.
  • Performance Measurement: Covering various techniques used to assess project performance, including cost, time, and quality metrics.
  • Project Forecasting: Techniques for predicting project outcomes based on current data and trends.
  • Risk Management: Understanding how delays and other schedule risks can be mitigated through proactive management.
  • Software Tools for Project Management: Discussing modern software solutions that integrate ES and EVM for project tracking and management.

Explore these topics for comprehensive insights into not only Earned Schedule but also its critical role within the broader field of project management and performance measurement.