Cumulative Flow Diagram for Azure DevOps

In the Cumulative Flow Diagram for Azure DevOps (CFD), the horizontal axis shows a timeline and the vertical axis displays the number of work items in your columns. Each colored area represents a column in your Azure board. The size of the areas indicates how many work items currently exist in each column.

To be able to achieve a stable process, strive to keep the number of work in progress within the WIP limits for each column.

By hovering over the graph, you can see the number of items in each process state on the selected date. You can also track the accumulated number of tasks completed, those in the Done state, in the selected time frame.

You can switch between “process” and “states” in your WIP tooltip to see your total WIP or the WIP in each list on your board.

Reading the horizontal difference between the top and the bottom line of a CFD area at any point along the graph will give you the approximate average cycle time of your completed tasks. It measures the average time that it took to complete all items on the selected date.

A comparison of the approximate average cycle time from your CFD with the exact average cycle time from your Cycle Time Histogram for Azure DevOps can give you a good understanding of your process performance. If these values are roughly equal, this indicates that you are maintaining a stable system.

The bottom line of your CFD represents the ‘Done’ state from your process. By observing that line, you can measure the amount of work your team has delivered. The gradient between any two points represents your average throughput. If your team is productive, you will see the ‘Done’ area grow rapidly.

Keep tabs on the gradient of your ‘Done’ area - the slower it grows, the longer your delivery times.

The graph’s top line represents the rate at which new tasks are coming in your workflow, while the bottom line depicts their departure rate. These are the rates at which you start new work and finish outstanding work.

You need to monitor these lines closely. To achieve a predictable workflow, strive to keep your WIP as consistent as possible. If your WIP is consistent, the arrival rate and departure rate lines will grow in sync.

The ‘Arrival and Throughput Rates’ widget on the Cumulative Flow Diagram for Azure DevOps enables you to track how your arrival and throughput rates change over a certain time frame. Ideally, you should see these lines overlap with each other.

A rising arrival line means that you’re starting work faster than you finish it and your team is working on more tasks than they are able to handle at a time. Higher arrival rate leads to higher WIP and usually results in increased cycle times and potential delays.

The Cumulative Flow Diagram for Azure DevOps enables you to evaluate the stability of your system and help you identify problem areas. In a stable system, the average arrival rate is roughly equal to the average throughput rate. This means that your workflow is predictable, as the tasks arrive in the process at the same speed as they are leaving it.

Based on Little’s Law, Average Cycle Time = Average Work In Progress / Average Throughput. Balancing this equation and adopting Little’s Law assumptions as explicit policies is the best way to establishing a stable workflow.

By using the Cumulative Flow Diagram for Azure DevOps, you can gain instant insight into the exact amount of work in each state of your process. If you find that one of the colored areas that represent WIP starts expanding, your diagram has honed in on a bottleneck in that state.

Remember, before you make assumptions, first consider the possibility of any changes like team size or a public holiday - these could explain the unexpected activity spikes.