How Trajectory deals with velocity
Trajectory calculates your current velocity by averaging the points accepted in the last three iterations. This number represents a good estimate of the number of points you can expect to accomplish in the current iteration. Trajectory also uses this number to break out upcoming stories into an estimated schedule.
This estimation strategy comes from the Agile principle Yesterday’s Weather.
For new projects, we set the default velocity to 20. This can easily be changed within the settings page for any project.
Use team strength to keep velocity accurate
There are situations that can cause the calculated velocity to be inaccurate. One case could be members of the team being on vacation during one iteration but not the next. You can account for these temporary reductions in effort by adjusting the team strength for an iteration.
As an example, if a team of five people has three members going to a conference during an iteration, you can set the team strength to 40%. The purpose of this setting is to adjust velocity calculations so that future iteration velocities and release planning can be more accurate.
Where do I set team strength?
Team strength is set on the iteration page, which can be reached by clicking on the date of the iteration on the story index. You’ll see an input in the sidebar that allows you to change the team strength for the iteration.
Note that this value can be more than 100%. This is useful for situations where you have extra people working on the project during that iteration.
When the team strength is not 100%, the value will be visible in the iteration header on the stories index.