BEIJING, Feb. 26 -- Ninety percent of the 161 Chinese cities monitored by authorities failed to meet national air quality standards in 2014, the National Bureau of Statistics (NBS) said on Thursday.

Despite decline in coal consumption, only 9.9 percent of the cities met national air quality standards through 2014, NBS said.

China consumed 2.9 percent less coal last year compared to 2013, and use of natural gas and electricity increased 8.6 percent and 3.8 percent respectively, according to an NBS report on China's economic and social development in 2014.

Hydropower, wind power, nuclear power and natural gas accounted for 16.9 percent of total energy use, while coal made up 66 percent.

China also strengthened efforts to protect the environment last year, adding 6 million hectares of forest and improving 54,000 square kilometers of land troubled by water and soil erosion.