Introduction to the Burndown Chart
The burndown chart is an Agile tool used to graphically illustrate the remaining effort in a sprint over a period of time. An Agile sprint is planned to accomplish a certain amount of work, or tasks, throughout its duration. The burndown chart allows the project team to easily measure the completed tasks against an ideal rate of task completion to gauge progress. This visual tool provides the project team with the ability to shift or re-focus resources in order to ensure all planned tasks are met for a given sprint. While there will be circumstances in which teams do not complete all planned tasks, the burndown chart provides a simple way to not only track progress during a sprint, but to quantify overall project progress.
The Components of the Burndown Chart
While burndown charts may vary slightly, there are some basic components which should be included in order to provide a good picture of sprint progress. Burndown charts should contain, at a minimum, clearly labeled title and axes, an ideal remaining task line, an actual remaining task line, and the daily completed tasks. These components are explained below:
- Title and Axes: While it may seem obvious, the burndown chart should have a suitable title and a clearly labeled vertical and horizontal axis. While the project team may be intimately familiar with the chart, stakeholders may not be so they need all of the available information clearly labeled so they understand what they’re looking at. The title should pertain to the project and/or individual sprint name. The horizontal axis indicates time and is usually labeled by each individual day of the sprint. The vertical axis indicates the number of tasks remaining and the number of completed tasks for each day.
- Ideal Remaining Tasks: Actual sprint progress needs a benchmark for comparison purposes. The ideal remaining tasks line is this benchmark. The simplest way to create this benchmark is to equally divide the total number of tasks planned for the sprint by the numbers of days the sprint is planned for and create a straight and constant line.
- Actual Remaining Tasks: This line tracks the progress of the team each day during the sprint. As the team completes planned tasks, the number of remaining tasks decreases. This progress line is used to show if the project team is ahead, behind, or on schedule by comparing the line with the ideal line. If the actual remaining task line in on the ideal line, then the team is on schedule. If the actual line is below the ideal line then the team is ahead of schedule. If the actual line is above the ideal line, then the team is behind schedule.
- Daily Completed Tasks: Some burndown charts do not track this number but it should always be included. This value represents the amount of tasks the team completed for each day. This is valuable because it allows the project team and stakeholders to see when progress is being made and provides an indication of how the project team is handling the planned work. For instance, if no tasks are completed for the first 5 days of a 20 day sprint, it may be an indication that the team doesn’t have a firm grasp of the work from the outset of the sprint. It may also indicate that more or better planning should be done prior to the sprint kickoff.
Sample Burndown Chart
While the burndown chart is always a graphical illustration, it is based on data tables tracked by the project team. Below is a sample data table that tracks the progress of the sprint through all 20 days.
The data table above is then graphed to provide the burndown chart on the next page.
The Sample Burndown Chart above shows the progress of the team through all 20 days of the Sprint. The horizontal axis shows time and is labeled for each of the sprint’s days. The vertical axis shows the number of remaining and completed tasks. For each day of the sprint, you can clearly see how many tasks were completed for each day (the orange bars) and the resulting number of tasks remaining (the blue line). You can also clearly see how the team’s progress on remaining tasks (blue line) compares to the ideal (green line) and see if the team is ahead, on, or behind schedule.