For a team new to agile software development, estimating user stories is not easy. The team is used to estimate tasks in hours and days, and know they’re never right anyways. So why bother? In agile, estimating user stories relative to each other using story points can give you a fact based idea about what will be done by when. But how can you do it?
Assign 1 Story Point For Fixing Typos
Usually, you start with the smallest story from the backlog. But how many story points it shall get? We are using PivotalTracker with a fibonacci scale for story points. In PivotalTracker the scale is 0, 1, 2, 3, 5, 8. For us, the smallest imaginable thing to change in our software is fixing a typo. This is what we would assign a 1. Now, we’ve got a reference point for our smallest user story from the backlog.
Assign 3 or 5 Story Points For Concrete Features
If we start from scratch, stories tend to be quite big. If you can tell exactly what needs to be done, you could give it a 3. If describing the story gets cloudy, but you still have a quite good idea what to do, give it a 5.
Assign 8 Story Points For “Epics”
If the story is completely abstract by now, give it 8 story points. 8 story points means: “This story is too big to really estimate it. It needs further investigation. Then we can break it down into a series of smaller stories”.
And What About 0 Story Points?
In PivotalTracker, chores (things which need to be done but do not create value for the user), have a simplified status flow. There is no “Accept” or “Reject” for them. If you’ve got to do bigger things which need testing, we use features as story type and assign them 0 story points. That way, the chores do not add to our velocity (exactly the way it should be: Clean up work should reduce your velocity, as you deliver less value for your users).
Estimation of user stories is always dependent on the team and the stuff to be done. The above guidelines have worked out for us in a couple of different scenarios. But your mileage will vary. What is your experience with estimating story points? Please tell us in the comments!