Suggestions for charting average durations?

Has anyone charted average durations before? I tried it with a pie chart, but when using averages, it is converting durations into decimals (I'm not even exactly sure what it is doing). Trying other charts, but wondering if anyone has already gone through the trial and error, and found any particular charts to be the most useful when trying to look at average durations.

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Mike Tamoush
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