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.

Flow efficiency measures the share of active days during the lifetime of an issue. Flow efficiency calculation considers only the business days within the lifetime.

This number helps you quantify focus: for a focused team, making steady progress towards completing the issue, the number will be close to 100%. On the other hand, for a team trying to complete too many work items at once, the number will be significantly lower. Increasing your flow efficiency helps you deliver value earlier and eliminate waste.

Related metrics

Lifetime

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.

Active days

The active days of an issue are the number of days on which the issue has had activity. Issue activity includes all effort-generating events tied to the issue, such as commits, pull requests, reviews, and issue-in-progress events, which capture when an issue status is in progress and assigned to an individual.

Flow efficiency excludes weekends from the efficiency calculation.

April 16, 2026 – The definition of flow efficiency was changed to include issue-in-progress events. In addition, initiatives and issues were updated to work identically.

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%

Flow efficiency excludes weekends

In contrast to cycle time, flow efficiency accounts for weekends. That is, if your issue lifetime is from Monday to the Friday of the next week, and there is version control activity on each weekday, the issue's flow efficiency will be 100%, even if there is a weekend in between.

This special handling of off-hours is so you have an intuitive target to aim for: less than 100% to avoid spreading your focus too thin; more than 100% to ensure your pace is sustainable.

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 poorly defined, leading 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.