Hang Reports Don't Add up to 100%

We have noticed that the hang reports provided in Xcode include the percentage of hang time, which are used to sort from high to low (effectively sorting by priority).

However when adding these percentages up we do not get 100%. For newer releases the total may be quite low (5-20%) but even for older releases we only get up to around 85%.

Are there reports we are missing? Is there a threshold or something that lower percentage reports are not hitting?

Any level of understanding here would be appreciated!

Hang Reports Don't Add up to 100%
 
 
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