Sorry for the ambiguity -- but no, I mean getting historical cost data retroactive to the resource creation would be great, but I can understand why that's not possible. What I'm saying is that Cost Allocation Tags specifically won't return any cost data for resources that are older than that CAT's activation date. So not only do I not get past costs but I don't get anything going forward. I went on a tagging spree a while back and then spent a bunch of time later down the road trying to figure out why it was getting info for some things and not others.
Is that how it works? It's been a long while since I first set up tags for Cost Explorer, but I'm fairly certain it must have applied to, say, pre-existing EC2 instances and so on or else I never would have had it working...
