Too rapid expansion.

[stormbringer3]

Twice in my early game I've taken a hit for this. What's the cause of the hit?
Thanks for any info.

[n0b0dy007]

Twice in my early game I've taken a hit for this. What's the cause of the hit?
Thanks for any info.

I'm guessing that you're seeing message pop up that says something like: "overexpansion is taking its toll and %{1}u civilization is regressing (aging tier reached)"

This is the Culture/Decadence Ratio (CDR) dynamic. The message arises from the faction slipping into the bottom 1/3 tier in the CDR rankings. See, for example, the Belgae in this list:

2020-06-14 15_40_40-Window.png (345.11 KiB) Viewed 948 times

Note the faction names in orange - those are the ones in the bottom tier of the CDR rankings (top-tier names are green, mid-tier names are default).

The solution is to invest more in Culture: build more purple buildings, put more (citizen) POPs on the 4th work line, disassemble decadence-producing structures, &c.

[stormbringer3]

Thanks.

[poesel71]

A solution for overexpansion is to:
a) get a client state
b) transfer all your rubbish regions to him
c) buy them back for units later or get them gifted eventually

Basically use the CS as a bad bank.