Earned Value Management has been used for many years and has evolved to a comprehensive, multi-dimensional approach to managing even the largest of projects. The U.S. Department of Defense has been using EVM for over thirty years to manage the schedule, performance, and costs of projects worth tens of billions of dollars.
However, at its core, EVM can be quite simple and provide significant value while focusing on just three aspects at any given point in a project:
Using EVM calculations on these bits of information illuminates the health of the project in terms of both schedule and cost.
Source: Defense Acquisition University