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In the horizontal axis (x axis) the period of time in days that the sprint lasts.
In the vertical axis (y axis) the amount of work planned for the sprint, in the unit of measurement chose to estimate: Story points, original time estimate or issue count.
REMOVE DONE BARS DESCRIPTION
Guideline, the grey line. This line is a guide for your team to approximate where they should be to finish the work on time, provided the work was done in a linear progress. The ideal amount of work left or ideal burn rate.
Completed work, the green line. This line indicates the amount of work done (either number of story points completed in the sprint, issues done or time).
Work scope, the blue line. This line is the work planned for the sprint. Here you should check if it increases, which indicates scope creep i.e., growth in the scope of the sprint.
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