Set a project's summarization options

Choose Enterprise, Projects.
Select the project you want to summarize.
Display Project Details, then click the Settings tab.
In the Summarized Data section, type the maximum WBS level to which the project can be summarized in the Summarize to WBS Level field. When P6 Professional is connected to a P6 EPPM database, this value represents the number of levels of data that will display in the Portfolios section of P6.

The Last Summarized On field displays the last time data were summarized for the project.