Project baselines are used to keep track of schedule changes. If a project manager decides to make a schedule change, but wants the ability to report on the data from before the change, the project manager can save a baseline prior to changing the schedule. There is no limit to the number of baselines that may be saved for a single project.
From within your project, select Options from the View drop down. Then click on the Project Baseline tab.
To save a new baseline, simply enter a name for the baseline in the Set Project Baseline input box and click Create New Baseline.
Baseline reporting will display baseline data for the baseline set with a Status of Current. Remember that the Current status reflects this as the current baseline to compare in reporting with the current project schedule. Choosing a different baseline for baseline reporting can be done using the Set as Current hyperlink on the line associated with the baseline you would like to use for reporting.
While task list displays and task reports are restricted to reporting only the current baseline, project reports have the option to display all baselines. To display baseline data in project task lists and reports, use columns and/or row settings in the Page Display Options.