Branch metrics estimate the completion of a certain branch in the story tree. There are two ways to calculate progress:

Leaf progress: Leaf stories
Done count The sum of all done leaf stories' story points under the story. "Leaf stories" do not have children.
Total count The sum of all leaf stories' story points
Branch progress: Estimated progress
In branch progress, the story's own story point estimate is compared to the sum of its children story points. The greater number is included in the estimate.