Rally has a field for Completion %. The request is to be able to pull this data into Aha! features for visibility into the Completion %.
You can now sync estimate and percent done fields between Aha! and Rally (CA Agile Central) for master features, features, and requirements — giving you a clear picture into the effort required for each work item.
Check out the blog post for more details.
Can you help with any timelines on when can we expect this to be released? Q1' 17 / Q2'17?