Using inSSIDer home version 3.0.7.48, I notice colored underscore lines beneath some of the channel numbers beneath the X-axis of the 2.4GHz "Channel Graph." These underscore lines are also shown in the example illustration at the end of the User Guide but do not appear to be mentioned in the guide's text. (Or am I missing something in my reading of the text?) What do the underscore lines and their colors mean?

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