Cost of living in San Luis Potosí (Mexico) is 18% cheaper than in Zhenjiang (China)
This comparison is lacking data. It provides a decent comparison, but it is not yet reliable. It is based on 117 prices entered by 16 different people.
For example, to keep the same standard of living that would require 8,200元 in Zhenjiang you would need to make just about 6,754元 (Mex$ 19,866) in San Luis Potosí.