Is it intentional?

That the Member's Online in the past 24 hours is a continous type of statistic/list? Most uses of the mod I've seen have it reset at a certain time, but is it set here to recount every so often through the day? The count has been going down for the past few hours...

 

There is a mod to show the the users in the last day (you define when that day starts) or in the last x hours. If you do it in the last x hours, then the starting point will be continually moving.

 

Ah, that explains a lot then. I must have set it on my own forum, and seen it on other forums as the 'within last day' rather than 'within x hours' option.

 

Yes, it is indeed set to "rolling 24 hours", so it isn't reset at midnight or anything.