Under the planned economy, when a worker retired, a son or daughter could take over the post. The system was called dingti (顶替), “taking the place.” It began in the 1950s. From the late 1970s, it was applied across the country to ease unemployment among urban youth.
In 1983, a State Council notice set out to regulate and restrict it. A study of the system notes that some parents even retired early, before they met the legal conditions, so that a child could take over.