[KGIII]

This article has some very different numbers. Also, it may be a small percentage but the total number of individuals is huge. There's a lot of Chinese people, after all.

Anyhow, link:

https://chinapower.csis.org/china-middle-class/

As for the numbers in that link, I'm not sure of the validity. I see lots of different numbers quoted at different sites. I have to wonder if it is accurate. A couple even put their upper middle class at 35%.

[chaostheory]

According to your article (unless I misread it) the lower class is 68% of the population. While it has greatly improved, there's still a huge gap

[KGIII]

Right, 32% vs. 18-20%. Which, in hard numbers, is quite a few individuals. Your post said 18-20%, so I figured I'd give you the current estimates for more accuracy. The estimates for upper-class were but 2%.

Probably important: There is some disparity in numbers. A few claimed higher, a couple had lower. Neither was significantly higher or lower, so I went with that one. Interestingly, a frequently listed number was 50% middle class by 2030.

My guess is that the numbers aren't accurately reported, which explains the variations.