If your team is using Kanban, you probably want to know how effective your team is when using this pull technique. The approaches of measuring team effectiveness in Kanban are numerous – it would probably be possible to list dozens of metrics designed to evaluate this technique. However, in order to keep it simple, we will discuss the two of the most common metrics used to evaluate Kanban performance – and will provide a few insights on what you can learn from them. These methods are Cumulative Flow Diagram as well as Lead and Cycle Diagram. The latter will be covered in another blog post.
Both of these metrics are supported at Eylean, so we will help you understand how to make the most sense of these metrics.
Cumulative flow diagram
The most common approach of measuring team performance at Kanban is Cumulative Flow Diagram or CFD. An example of Cumulative Flow Diagram is described below.
Cumulative flow diagram shows the tasks at each stage of the project over time. For example, the green area represents the tasks that are completed. In the chart above, it seems that there was a large jump in the number of tasks completed on days 18-22 and then continued to grow only gradually. The red area represents items in progress, while the blue area covers the tasks ready for development.
Cumulative Flow Diagram may seem complicated at first, but at a closer look it can easily show a number of useful insights. For example, the vertical axis of the chart shows how many tasks are currently being worked on or completed. It allows understanding the optimal work in progress limits.
The horizontal axis shows the Cycle time – or the time required to complete one task. Knowing the time needed to complete a task, makes it possible to estimate the time required to finish the whole project.
What should you look at when you see a Cumulative Flow Diagram? Well, first of all note if the work in progress area is growing or staying constant over time. If the work in progress area is increasing, it means that the team cannot handle the workload and it might make sense to review team size, project specifics or the company situation.
Secondly, you should note the steepness of the curve in the done area. If the curve is flat at certain periods of time, that should warn you that the team is either working on more complicated tasks or is less productive.
Thirdly, Cumulative Flow Diagram also shows Lead time and Cycle time. Lead time is the distance between tasks ready to be done and done, and shows how much time elapses from a request from the product owner until the task is actually delivered. Cycle time is the distance between work in progress and done, and shows how much time each task actually takes.
Ideally, the Cumulative Flow Diagram should smoothly slope upwards, without breaks, jumps or flat periods – as that indicates a smooth flow of the project.
So what should you do if your Cumulative Flow Diagram is less than smooth?
First of all, it is possible to lower the work in progress limit. If there are less tasks in progress, they tend to be finished more rapidly, and hence contribute to a streamlined, smooth team performance. Secondly, in case there are large jumps in the curve, you can also decrease the scope of each task. If the tasks involve large volume of work, the output is not flowing smoothly and thus bottlenecks may arise. Thirdly, you should try shorten lead and cycle times, to make sure that the tasks are completed at higher velocity.