I should have been more specific. Rural, or cities below a certain tier, in general, often means very poor in China. The ethnic minority areas are very rural

I should have been more specific. Rural, or cities below a certain tier, in general, often means very poor in China. The ethnic minority areas are very rural and far away from places that generate wealth. It's not because they're minorities in an American sense, the government there actually gives ethnic minorities a lot of extra privileges, they get to have more kids, etc. There's a form of affirmative action where they're "bussed" to other areas, which of course gets reported in the west as yet another form of repression. Not speaking Chinese is going to be an obstacle to getting ahead in general. I don't have a cite, this is all based on conversations I've had and what I've seen of rural reality in China (haven't been to Tibet, Xinjiang or Inner Mongolia, but I've seen some really crappy lifestyles for rural poor Han Chinese. And they thought things were going great! Much better than in past decades).