So, this might have caused a few issues.
In the clan information infobox template, I've changed 'Population' to 'Total Population' and added a new row called 'Average Population.' The idea is that you wouldn't have both on one article, but only use the one that was necessary. Most older, dead clans probably need 'total population' because we have no chronological data on their membership count. However, we can figure out everyone who was involved, or at least as many people as we can find. Calling that the 'total population' helps us understand that this may not have been how many members that the clan had at any given time, but rather over the entire course of its existence.
However, for a clan like the New Lunar Republic that has chronological population records, we can find an average population and use that number instead. The same goes for the LittleBigPlanet Union.
I also just want to make clear, but no means is this an attempt to point out that clans that recorded their population over time are 'better'. That's just not true lol, there were a lot of great clans that did not record their membership over time. I wish that they did so that we can know that information, but it's just not something that anyone thought of back then. There's also other information we have to worry about like artificially inflated membership counts (I'm looking at you, Armageddon Empire .)
This all being said, the change may cause some issues with some pages on the wiki. Be on the lookout if you see something under 'Total Population' that is actually an average.