(upbeat music) In these lessons, we'll discuss progress updates, how and when to take corrective actions when required, how to forecast project completion, and how you can best control a schedule. A baseline is a fundamental concept in controlling a project. A baseline is a saved copy of the project plans that won't change. When the schedule is approved, it's time to make a baseline copy. You can use it to measure progress against the schedule as work is completed. For example, suppose you are using a software tool for the schedule. In that case, the application will save critical data points, including the start date, end date, duration estimates for each task, and other plan elements. The project manager can then examine project tasks and compare the plan's start date, end date, and duration to what actually happened. The difference between the plan and the actual data is known as a variance. It's also crucial to check the project end date. As tasks on the critical path slip out, the project end date will be effected. The interval for measuring project progress to keep it on track is usually a week. Status reports and other project updates may not be that frequent. Still, the project manager needs to check variance regularly. For any well-planned project, some tasks will take more than the planned time, and others less. It's critical for the project manager to look for trends or large amounts of variance. These show a need for corrective action so the project can finish on time. A variance may be positive or negative. Negative variance indicates the project may be falling behind. Positive variance suggests the possibility of early completion. For many projects, early completion may cause issues including additional storage costs, early progress payments causing cashflow issues, and idle resources. Still, early completion is better than late completion.