Just as the Sprint Burndown Chart indicates whether a sprint will finish on time, they say that the Product Burndown Chart provides an indication of how quickly the team is delivering Product Backlog Items, allowing the team to predict how fast it can deliver future items. To date, we have not used one at Decade Software Company, but marketing really needs us to—so we've excepted the challenge this week.
Here's how it will work:
The chart works from two pieces of historic data:
- The Estimated Effort for each Product Backlog Item
- The date that the Work Remaining for a Product Backlog Item became zero
The Work Remaining section of the column shows the total estimated work as it was at the end of the Sprint.
Provided that estimates are not changed and work is not removed, the total height of each column will be the same as the height of the previous Sprint's Work Remaining section.
The Linear Regression line shows the trend, and the point at which it crosses the X-axis shows the best estimate for when the Product will be complete. The data for the trend line is the set of points representing the Work Remaining for each Sprint, together with the initial starting point.
If the outstanding work is changed dramatically through re-evaluating the work or time allotted, the Linear Regression line is likely to provide a pessimistic prediction for completion time. However, as time moves on, and the trend line reflects Sprints where the estimates have not changed, the intercept with the X-axis will become more realistic.
Clicking on the Burndown section of a column, allows you to "drill through" to the Delta report for that Sprint. This shows a breakdown of the Product Backlog Items and the changes (deltas) in the Work Remaining for each.
From what I hear, this Scrum tool is the least used, so ironically there is little historic data to prove the chart works. Watch this space to see how we fare—and wish us luck.
You mean 'accepted'. Surely.
Posted by: bob ama | May 04, 2009 at 01:51 AM