Cumulative Flow Diagram

When you think about the Kanban Method, chances are the first thing that comes to mind is a Kanban board. But the Kanban Method is much more than just a tool for managing work visually. In this article, we'll look at one of the other key concepts in Kanban: the Cumulative Flow Diagram (CFD).

What is a Cumulative Flow Diagram?

What does it measure?

A Cumulative Flow Diagram (CFD) is a graph that measures the amount of work in a system at any given time. The x-axis of a CFD represents time, while the y-axis represents the number of items in each state of a workflow. For example, if we’re tracking the development of a software project, our workflow might have the following conditions:

• Backlog: Items that have been identified but not yet started
• In progress: Items that are being actively worked on
• Done: Items that have been completed

Using a Cumulative Flow Diagram can help you identify bottlenecks in your workflow. For example, if you see that the number of items in the "in progress" state increases over time, something is preventing those items from being completed. By identifying and addressing these bottlenecks, you can improve your system's overall workflow.

What is throughput?

Throughput refers to the amount of work that flows through a system over time. This can take many different forms, depending on the workflow being measured. For example, in a software development project, throughput might be measured as the rate at which new features are released, or code is merged into the main branch.

Understanding throughput is essential because it can help you optimize your workflow and make better decisions about allocating resources. If you see that throughput is decreasing over time, your team may have reached its capacity and needs additional resources to meet demand. Conversely, if throughput increases rapidly, it may be necessary to re-evaluate your workflow to ensure that quality is not being compromised.

What information does a cumulative flow diagram provide?

A cumulative flow diagram provides a snapshot of your workflow at a given time. It can help you identify bottlenecks and predict how much work will be required to complete a task.

What happens when bands are close together, and what does it mean? 

If the bands are close together, the cards being put into the sprint are completed quickly. This generally means that the process is running smoothly without any bottlenecks. As a result, there’s some free space in the team’s sprint backlog, and the team can start taking on more work. 

What happens when bands are far apart, and what does it mean?

If the bands in your Cumulative Flow Diagram are far apart, it implies that cards being put into the sprint are stuck in progress or are taking too long time to complete. This could be due to bottlenecks in the workflow or simply because there isn't enough capacity to handle all of the work flowing into the system. In either case, it's crucial to identify and fix the issue as soon as possible.

What happens when bands are progressing in parallel, and what does it mean?

If the bands in your Cumulative Flow Diagram are parallel, your throughput is stable since new cards are being completed at roughly the same rate as old cards. The team’s work is being completed steadily, and there aren't any significant bottlenecks or delays. This can be a sign of good process health and may indicate that your team has enough resources and capacity to handle all of the work coming into the system. 

Where can I create a CFD?

Trello

Trello's CFD is built into their product backlog board. To create a Cumulative Flow Diagram in Trello, click on the "Backlog" board, then click on the "Cumulative Flow" tab at the top of the screen. From there, you can select the date range that you want to view and see how work has flowed through your system over time.

Excel

In Excel, you can create a Cumulative Flow Diagram by using a line chart. To do this, simply create a line chart with your data, then add a trendline. In the trendline options, select "Linear" and check the "Display Equation on Chart" and "Display R-squared value on chart" boxes. This will add the trendline equation to your chart, which you can use to calculate the flow rate.

Lucidchart

With Lucidchart, you can create a Cumulative Flow Diagram in just a few steps. First, click on the "Diagrams" tab at the top of your screen, then select "Flowchart." Next, simply drag and drop shapes to create your chart. Once you've finished creating your chart, you can save it as an image or export it as a document to share with your team and stakeholders.

Final Thoughts

Cumulative Flow Diagrams are a powerful tool for visualizing workflows and identifying potential bottlenecks or delays that may impact your team’s productivity. By monitoring these diagrams over time, you can make proactive adjustments to optimize your process and ensure that tasks flow through your system as efficiently as possible.

GoRetro is a powerful retrospective tool online that can help Scrum teams create and track Cumulative Flow Diagrams. With GoRetro, you can easily conduct sprint retrospectives to reflect on individual and departmental activities, making future initiatives operate more efficiently for everyone. Visit our website today to learn more about how GoRetro can help your retrospective process.