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You can toggle the chart parameter data on or off - this can be useful if you need to take a screen-grab for a presentation.
Select which states 
you want to see the data for.
Each column represents an issue with the height 
being the number of days in that state. The colour shows whether it is a story, a bug or a blocked story/bug.
The red line shows the mean time that issues have been taking to get across that state in the previous 30 working days.
Clicking on the bar shows the details of the item and enables you to click and open it up in JIRA.
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