BEIJING, Dec. 17 (Xinhua) -- Beijing's permanent residents continued to drop in 2018, as the migrant population in the city slid for the third year, according to a recent report.

Beijing's migrant population was 7.65 million in 2018, down 3.74 percent year on year. The population dropped 1.84 percent and 1.63 percent respectively in 2016 and 2017, according to the report released by the Beijing Administration Institute (BAI) and the Social Sciences Academic Press.

The number of permanent residents in the city totaled 21.54 million in 2018, down by 0.76 percent year on year, it showed.

Beijing plans to cap its population as it seeks to address "big city diseases" such as traffic congestion and pollution.

Ma Xiaohong, who heads the Beijing city studies center in BAI, said the population drop reflected the success of the city's efforts toward high-quality development. "In terms of age structure and education levels of the population, Beijing has its clear advantages compared with the national average."