Are you 100% sure? Because, now that I think of it, I've never seen mining income at 2000, even when my minds were upgraded. Regardless, I was making good money, so I didn't care too much, and didn't give it another thought.

I didn't realise the descriptions you see on the screen and those governing mechanics were inter-related. That seems silly to me, really. Another hardcoded gift from the CA gods, yes?