@Riot: What is the average lifespan of various races in Runeterra?

Poppy's new lore indicates she's probably hundreds of years old, as she was around during Demacia's beginnings. Thus we can conclude that Yordles probably live several hundred years, if not over a thousand (barring any unfortunate ends).

In the meantime, Lissandra is clearly thousands of years old, but can justify this by not being human anymore, and being given immortality by the Frozen Watchers. Meanwhile, Xin Zhao's lore (which is outdated, but may still count) shows he was around since the age of Jarvan II, and has protected Jarvan III even into his elder years (yet Xin looks barely 40). And let's not even get started on Master Yi; who knows how old he is.

I think, Riot, that we need to form some kind of consistency for racial age expectancy in Runeterra. Humans seem to be inconsistent on how long they can live, and trying to peg life expectancy down for various races bugs me to no end.

Is there any way you could give us a life expectancy range? Or does that violate your NDA?