A burndown chart shows the amount of work that has been completed in a sprint, and the total work remaining. It gives you a visual representation of how your sprint is going and is used to predict your team's likelihood of completing their work in the time available. 

Burndown charts are useful because they provide insight into how the team works. For example: 

  • If you notice that the team consistently finishes work early, this might be a sign that not enough work is committed to during sprint planning. 
  • If the team consistently miss their forecast, this might be a sign that too much work is included in the sprint. 
  • If the burndown chart shows a sharp drop during the sprint, this might be a sign that work has not been estimated accurately, or broken down properly.


You can access the sprint burndown chart by clicking the Burndown Chart link on the sprint board page.



Below is an example of a burndown chart where the sprint is predicted to finish one day late based on the current progress.



The burndown chart consists of multiple data points. The descriptions below explain how each of these data points is calculated. 


Target Burn 

  • This line represents the estimated number of points remaining to be completed for each day of the sprint if all the sprints tasks are to be done before the sprint end date.
  • The line is a straight line from the total number of points on the first day of the sprint to 0 points on the sprint end date.


Points Remaining

  • This line shows the sum of points still to be completed. 
  • Compare it to the Target Turn line to see how the sprint is progressing.


Predicted end

  • The predicted end date based on the team velocity (see next section to learn more about velocity).
  • The predicted end date is calculated as follows:
    Sprint End Date + ( (Total Points - (Completed Points + (Days Left * Velocity))) / Velocity ) 
  • The predicted end date is shown as a line from today's Points Remaining value to the predicted end date.


Value Completed

  • This line shows the progress of completed business values during the sprint.
  • This line shows the sum of business values of tasks that have been completed since the beginning of the sprint.


Predicted Value

  • This line helps you visualise the expected business values completed at the end of the sprint.
  • It is a straight line from today's Value Completed data to the sum of business values of all tasks assigned in the sprint.



Velocity


This is a useful planning tool for estimating how fast work can be completed per day. The metric is calculated by reviewing work the team successfully completed during previous sprints; for example, if the team completed 20 tasks during a 10 day sprint and each task was worth 3 story points, then the team's velocity is 6 points per day.


If you know your team's velocity then this value should be entered for the sprint velocity (Backlogs -> Edit Sprint -> Velocity)

  • If the velocity has not been configured the graph uses this formula for velocity: TotalPoints on first day of sprint / Number of days in sprint.
  • If the velocity has been configured then the graph uses velocity value that has been entered as the points burn value.