Summarize the value of Custom Fields and aggregate data within your project. Some great ways to use rollups are:

The Status rollup will total all of the values of the selected field into the header of the Status.

You can enable Status rollups through a Status' hover menu, selecting Add rollup field, and then selecting the field from the project that you'd like to see totaled.

Once enabled, the total value of the selected field attributed to the Tasks within the Status will reflect in the Status header.

When a rollup is selected in your Roadmap, the total value of the selected field attributed to the Tasks within each Milestone will reflect in the Milestone sidebar.

Completed Tasks within the Milestone are also attributed to the Milestone's rollup total.

You're also able to visualize these rollups in your Project's Dashboard. To do so, open your Widget selector and choose the Rollups option.

Next, select the rollup(s) that you'd like to see as a widget on your Dashboard.

Note that you can have multiple rollups widgets enabled.

Once enabled, the widget will show the total value of the field amongst all Active and Completed Tasks within the project.