Flow efficiency

The flow efficiency of an issue is the percentage of days when the issue was actively worked on compared to its whole lifetime.

Related metrics

The lifetime of an issue is the amount of time between its first and last activity, according to merged data from your issue tracker and your version control system.

The active days of is the number of days on which an issue had some activity, either on GitHub or your issue tracker.

Issue activity includes all events that can be tied to the issue in question, such as commits, pull requests, and reviews. Issue status changes also count as activity.

Flow efficiency does not count weekends against the efficiency calculation, issue cycle time does include weekends.

Initiative lifetime

The calculation of an initiative's lifetime differs from the issue one. The initiative counts events when marking an issue as completed or when merging the first pull request associated with that initiative. Consequently, both the first and last activities of the initiative will be counted from that point onward.

Summary

Flow efficiency measures the share of active days during the lifetime of an issue. Lifetime includes only business days (weekdays, excluding weekends).

Example

If an issue from your issue tracker was opened on May 1st and completed on June 6th, we would first calculate that it had a lifetime of 36 calendar days. However, for the purpose of flow efficiency, we consider only business days (weekdays, excluding weekends). Suppose there are 26 business days in that timeframe. Then, we look at how many of those days had recorded activity—either from child issue movement or GitHub activity—to determine the number of active days.

Let’s say there were 10 active business days. The flow efficiency would then be calculated as:

(10 active days / 26 business days) × 100 = 38%

Why it matters

Low flow efficiency also indicates problems with focus and context switching, which can negatively impact developer experience. This also means you likely could have shipped sooner, and delivered value to your users more quickly.

How to use it

If you notice an issue has a flow efficiency of less than 80%, have a discussion with your team about what caused that. Was it because there were too many other work items in progress? Was the initial piece of work not well defined, which led to bottlenecks and scope creep? Depending on the answer, you can then take steps to improve in future cycles. There could also be an opportunity here to adopt a working agreement for your team to help drive higher flow efficiency.

Where to find it

You can find flow efficiency (and other flow metrics) by opening an issue popup anywhere in Swarmia where you see the name of an issue.