I just wanted to know; if a banner reads something like "combine 1 billion citizens with a strong economy", does that mean that you have to reach that goal before you get that population, or you're locked out of getting it forever? Or would 1 billion just be the minimum needed to attain that banner?
-Queen Ashley Ninelives the First Anthropomorphic Cat Queen of Superbunny
The East won the West not by the superiority of its ideas or values or religion … but rather by its superiority in giving native tribes fatal illness. Easterners often forget this fact; non-Easterners never do.
No you don't need to reach required economy level before hitting the pop requirement to earn the banner. Banners are earned when a certain stat (or stats) get past the threshold. You won't be locked out of the banner, because the game only checks your pop and economy stats for this one. It doesn't check if one stat requirement was achieved before the other.
"Achieve x population and y economy" simply means "get your economy level up to here and play the game for that many days".