I'm not 100% certain. But looking at it.. looks like it uses the total people online as the high point. So if there were 60 people max online (40 users and 20 guests) it won't update again until there are 61 users online (even if that's 30 users and 41 guests). Otherwise if it bumped the total of one of them.... then the total wouldn't match the total number of people online. That's what it's really tracking. It just gives the breakdown for some extra info.
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