How to show percent of sub-tasks completed in Sprint board?

[Coco S Chaussée]

One of my end-users utilizes sub-tasks a lot, and would like to have an identifier (either in percentage or numbers) for what's done/remaining.

The information is visible in a story or task detail already, so how can we add it to a card on the board?

[Randy · Accepted solution]

You cant.  This isnt supported, though it's a great idea.

Options to get you close include:

* ordering swimlanes by story so you visually see cards remaining per story

* scripting hacks to surface a custom field that has a calculated % value of subtasks closed.

[Antonie Rossouw]

How would one do this - * scripting hacks to surface a custom field that has a calculated % value of subtasks closed?