for Chinese population census data 1990, which industry classification the variable "ind" follows?

For Chinese population census data, 1990, harmonized version. I realized the varibale “ind”, with lable “industry, unrecorded”, does not match Chinese industry classification in 1990 nor IND1990 listed by IPUMS. May I ask which industry classfiication does this varible follow? Thank you very much.

In 1990, the Chinese Census used the “GB 4754-84” Industrial Classification for National Economic Activities. You can find the classification system in its original language here.

Hope this helps.