I was looking at the Top Users page on a particular tag and I saw that it showed that in the past 30 days I had answered two questions for a total score of 3:
This seemed odd, as I had recently answered a question in this tag that has a score of +7 (i.e. more than the total of all my answers in the past 30 days according to the listing). At first I thought that it might not be counting my most recent answer (i.e. the system might only update every so often and it had not updated since my last answer), and indeed in this answer it is claimed that it gets updated at midnight UTC.
However, if you don't count my most recent answer then I have only one answer within the last 30 days. As you can see in my profile, my previous answer in this tag (prior to the one that is definitely being counted) was back in August, which is well more than 30 days ago:
The Top Users listing must necessarily then be counting my most recent answer, and it is counting it as having a score of +1. I then thought that perhaps if it updated at midnight then it might have only had +1 at midnight with the other upvotes coming on the next day. However, the timeline of the answer shows that all the upvotes came on the same (Stack Exchange) day:
In fact, if you look at the timestamp of the answer you can see that it was posted less than two hours after midnight. I am almost 100% certain that more than one of the upvotes came within the first 22 hours.
It is also worth noting that it seems to be only the "Last 30 Days" column that has this issue; the "All Time" column lists my score as 292, which seems to be up to date as that is what it shows in the tag page of my profile:
So, is there a bug in the calculation of score for Top Users? Or is there some other calculation of the updates that explains how it would have been updated when there was only one upvote on the answer?