debt 80% rule = an average across all trade lines? or 80% rule on "each" individual trade line

Your credit website info is fantastic! Thank you for posting this info. I'm 40...
and never knew about the 80% rule.
Do you know if the major component of the 80% rule is:

1. an average across all trade lines? or
2. 80% rule on "each" individual trade line?

It's probably both...but is the larger component an "avg across all trade lines"?
Thank you.
REAL PERSON
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The rule is for each trade line...
Not the average of all trade lines.
thanks for the compliment.
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