Beijing has seen a steady improvement in its air quality this year, according to official data.

The average concentration of PM 2.5, an air pollutant, dropped to 42 milligrams per cubic meter in the first three quarters of 2019. This signified a year-on-year decrease of 10.6 percent according to an air quality report released by the Beijing Municipal Ecological Environment Bureau.

During the first nine months of this year, the number of days with air quality above standard reached 165, accounting for 60.4 percent of the total. There were only three days with heavy air pollution, five days fewer than last year, according to the report.

China's capital city has been plagued by air pollution and smog in recent years. But, Beijing has strengthened its efforts in combating air pollution. In the first three quarters of 2019, 33,700 heavy-duty diesel trucks were taken off the road and 58,000 electric vehicles were added, bringing the total number of new energy cars in the city to 292,000.

Dust control is another major aspect of Beijing's campaign against air pollution. From January to August this year, the average dustfall in the city declined by 21.6 percent when compared with the same period last year.

In addition, the city also removed 399 polluting companies in the first nine months of 2019, exceeding the yearly target.