Project Duration Forecasting …a comparison of Earned Value Management methods to Earned Schedule

Abstract: Earned Value Management (EVM) methods for forecasting project duration have been taught in training courses and used by project managers for four decades. These EVM methods are generally considered to be accepted practice, yet they have not been well studied and researched as to their predictive capability. Using real project data, this paper examines and compares the duration forecasts from four EVM methods to the Earned Schedule prediction technique. During the spring of 2003 the concept of Earned Schedule (ES) was introduced, demonstrating the possibility of describing schedule performance in units of time [1]. ES facilitates time-based analysis of the schedule employing uniquely the Earned Value Management (EVM) measures of cost. One year subsequent to the publication of ES, the concept was extended to include project duration forecasting [2]. This paper put forth two equations for forecasting the final duration for a project; one of which is used in this study. In the time span from year 2004 through 2007, two independent papers were published investigating the capability of the ES forecasting method. One paper writte