The Pull requests size graph displays the number of changes inside a merged pull request. Essentially, it measures the team's ability to separate tasks well.
You can view this data by day, week, or month. Please note that the display of the last six months or the last year does not allow the display by day.
Example of use
For the following graph, the period displayed corresponds to the last three months, and the display mode is by week. Overall, we can see that the merged code reviews per week have, on average, 10.5 changed files. Although variations are inevitable, we see relative stability here (according to the trend shown by the red dotted line).
Since this graph is interactive, hovering over it with your mouse will display more details for a given week (depending on the display mode selected).
Reducing the pull requests size helps the team by preventing bugs, allowing them to give better feedback, and making them easier to test.
Psst! Larger pull requests tend to have fewer comments and have less thorough reviews, thus potentially decreasing code quality and introducing more problems and bugs.
To learn more about the variation indicator and its calculation, check out this article!