Shanghai saw a decline in migrants in 2015, the first time in 15 years, according to a report published by the city's statistics authority.
The city had a population of about 24.15 million last year, 104,100 less than in 2014, the report said. Some 9.81 million migrants lived in the city last year, 147,700 fewer than 2014.
Shanghai-based Dragon TV reported that the city's economic transition from low-end manufacturing to high-tech and service industries, as well as rising living costs have caused the population of migrants to fall.
Many worked in the suburbs, such as the Jiading, Songjiang, Qingpu and Minhang districts in the past. But in recent years, the transition of industries in the suburbs, caused many to leave, the TV station reported.
A robotic company has acquired a floorboard factory occupying about 10 hectares at Malu town in Jiading district, and the floorboard factory used to hire more than 500 workers, the station said.
Chen Qiang, a deputy head of Baoqiao village in Malu town, told Dragon TV that about 6,166 migrants lived in the village in 2014, but the figure reduced to around 5,300 last year. Most worked in factories there.
Xupu village in Minhang district demolished illegal buildings covering 577,000 square meters in recent years, and the number of migrants living in the village has fallen from 30,000 to 15,000.
One migrant said rent for a room was 800 yuan last year, double that of 2014 which caused many migrants to leave.
Shanghai has planned to restrict its population to 25 million by 2020. The city has taken measures such as upgrading industries, improving public services and enhancing law enforcement to achieve the goal.
Peng Xizhe, director of the Center for Population and Development Policy Studies at Fudan University, said Shanghai should be careful in managing the population structure, such as different occupations and ages, to fulfill its goal.