Photo taken on Dec. 31, 2008 shows a view of a street under the blue sky in Beijing, capital of China. Beijing had 274 blue-sky days this year, 28 more than last year, meaning that air quality in the capital improved for 10 consecutive years, according to Beijing Environmental Protection Bureau. (Xinhua/Luo Xiaoguang) Photo Gallery>>>

    BEIJING, Dec. 31 (Xinhua) -- Beijing had 274 blue sky days this year, 18 more than the target, meaning that air quality in the capital improved for 10 consecutive years.

    "We fulfilled the target 31 days in advance, which is the earliest since 1999," Beijing Environmental Protection Bureau deputy director Du Shaozhong said on Wednesday -- the last blue sky day in the year.

    Beijing met its 2008 target of 256 blue sky days on Nov. 30. The city had 246 blue sky days in 2007.

    From January to November, major pollution indices like concentrations of sulfur dioxide and carbon monoxide fell by up to 27.8 percent, according to the Beijing Environmental Protection Monitoring Center.

    Beijing has a five-grade classification of air quality on the basis of these pollution indices.

    A reading below 50 is "excellent," from 51 to 100 is "fairly good," 101 to 200 is "slightly polluted," 201 to 300 is "poor" and more than 301 is "hazardous." Days with excellent or fairly good air quality are counted as blue sky days.

    Du attributed this year's improvement to the long-term effects of the consistent pollution control measures since 1998. Since 1998, the capital has invested more than 15 billion U.S. dollars to improve air quality.

    The city aims to have at least 259 blue sky days next year.