This discussion concerns a technical problem that is effectively insoluble, and therefore further group discussion isn't going to bear fruit. If you'd like to ask more technical questions, feel free to contact User:CzechOut directly.
There's a problem with the last three names on the list: Bear McCausland, Ellie Darcey-Alden and Joseph Darcey-Alden. Something seems to be wrong with their age templates. I've had to remove them temporarily to keep the list readable. Any suggestions for what to do?
I tried to add another name to the list but when I did, this appeared next to Joseph Darcey-Alden's name: Template:Number table sorting/positive. Could it be that there's simply too much data on the page? I'm afraid I don't have enough understanding of how the wiki works to be able to tell what's wrong.
If the problem is length, I suppose one solution would be to split the list in two i.e. have the first half be for people born between 1900 and 1949 and the second half for 1950 onwards. Just a suggestion.
When I try to add a new name to the list (as it is now), the aforementioned template appears next to the last name on the list. Trying to add more than one name results in the template appearing next to multiple names towards the bottom. I could be wrong but I think it might have something to do with the size of the list. That's why I proposed splitting it in two.
Regrettably, I have to inform all users who like these list of <whatever> by age pages that such lists simply cannot be processed efficiently by the software available to us. Not only are page load times astronomically high, but they easily reach a length where they can't properly calculate age anymore.
This has nothing whatever to do with the missing template that SOTO talked about upthread. That template, though now added to our database for completeness, was a simple rounding template that has no meaningful bearing whatever on the parent template, Template:Age in years and days.
The goal of the page in question is to have a single list of BTS personnel organised by age. That goal is impossible on a Wikia wiki. The age calculation template starts to significantly degrade after about 100 calls on a single page, and the cast and crew page has way, way more calls than that.
Since the goal of the page cannot be achieved, the page, and others like them, will shortly be deleted.
Before I do that though, I want to give you guys adequate time to see the proof. You can tell the page used to work by looking at the very first revisions. There, when the list was relatively small, the age was displayed correctly. Also, List of Doctor Who television writers uses the same age template, and it works out alright because there aren't nearly so many television writers as there are cast and crew.
Beyond the technical problem, however, lies the fact that really such things have been voted off the wiki. We decided some years ago not to try to maintain data about the age of real life people, because there simply is no good source for such information — at least nothing that would pass muster at T:VS. Actors routinely lie about their ages in order to stay employed, so they definitely aren't sources for their own ages. I know, Slughorn42, that you love finding out people's ages, but really, it's important that you stop publishing age related information on this wiki. You're kind of undoing the work of removing age data that has already been carried out to date.
Don't get me wrong: your enthusiasm for the subject is great! But it's just not information that we can either philosophically or technically use. It's important, too, that all editors understand that I'm not saying Template:Age in years and days should never be used. I'm just saying there's a limit to the number of times that the template can be used on a single page.