When I annexed a planet, it came with huge financial loss (more than -3000 credits). I was broke for several turns. Is this intended behavior? Since annexing is kinda automatic, at least some warning that it's gonna financially ruin you would be nice.
I believe it is some kind of weird bug. I have seen that once, going under for -3500 credits while I was generating 50bc per turn... But I tried to reload to reproduce the behavior and it didn't happen again. Very hard to file a bug report for something so random.