Indeed, I was of course looking to see a statistic on when the Monk's are most active (are we living/working at night or during the day?) in their own timezone.

Silly me, I overlooked the fact that server stats deal with load on the server. Mea culpa

For "easy" graphics have a look at Apache::GD::Graph. I used it with great success and I'm no graphic artist either.

All these statistical numbers help you to better understand the data as a whole. You can have different data with the same average value but a different standard deviation and this will tell you something about the spread of the values through the data. So -IMHO- it does add something.