Beijing witnessed an increasing number of days with blue skies in 2014, a clear improvement in air pollution control, while the reduction in the average concentration of PM2.5, a major air pollutant, failed to reach the annual goal by a hair, the municipal environmental watchdog said on Jan 4.

This year, Beijing will continue to keep a tight rein on air pollutants. It aims to reduce the concentration of PM2.5－airborne particles smaller than 2.5 microns in diameter that can penetrate the lungs and harm health－by 5 percent, a goal that the capital is confident of reaching.

Last year, Beijing had 204 days with air quality exceeding the national standards－20 days more than in 2013. In addition, there were 45 days with heavy pollution－the average concentration higher than 150 micrograms per cubic meter－down from 58 days in 2013, according to the report of the Beijing Environmental Monitoring Center.

“The increase of blue skies and decrease in pollution days show our measures on air pollution control are effective,” said Fang Li, deputy director of the Beijing Environmental Protection Bureau, the environmental watchdog, on Jan 4.

Additionally, Beijing has been the only city in China that has accomplished the targets set for four major pollutants (sulfur dioxide, nitrogen oxide, chemical oxygen demand and ammonia nitrogen) in air and water in 2014, which were targeted for the end of 2015.

In spite of the tighter rein on air pollution, the reduction of PM2.5 last year did not meet the goal set at the beginning of 2014.

The annual average concentration of PM2.5 was reduced to 85.9 micrometers per cubic meter last year from 89.5 in 2013, a decrease of nearly 4 percent, said Zhang Dawei, director of the Beijing monitoring center.

Under the Government Work Report released in January last year, the capital was to have cut the average concentration of PM2.5 by 5 percent, meaning it should have been lower than 85 micrometers per cubic meter last year.

“There are complex reasons making the reduction of PM2.5 lower than expected, such as the weather changing in a short period,” said Fang, adding that measuring the average concentration of PM2.5 over a longer period, such as three years, can be more useful and stable.

The municipal government has set a goal of reducing PM2.5 by 5 percent this year, which the environmental watchdog is confident of reaching, Fang said.