BEIJING, Jan. 20 -- China's working-age population dropped 2.44 million to 919.54 million in 2013, the second straight year of decline, the National Bureau of Statistics (NBS) said on Monday.

The working-age population, which covers ages between 15 and 59, took 67.6 percent of the country's total population in 2013, down 1.6 percentage points from 2012.

In 2012, China declared its first absolute drop in the working-age population in "a considerable period of time."

Those aged above 60 took 14.9 percent of the total population to 202.43 million; those aged above 65 took 9.7 percent of the total population.

By the end of 2013, Chinese mainland's population stood at 1.36072 billion, with a natural population increase rate of 0.492 percent.

The long-term rural residents stood at 629.61 million at the end of 2013, down 12.61 million from the previous year. The long-term urban residents hit 731.11 million at the end of 2013, up 19.29 million from 2012.

The urban population took about 53.73 percent of the total population, up 1.16 percentage points from a year earlier.

The gender ratio was 105.10 (105.10 males vs 100 females) with 697.28 million men and 663.44 million women.

The gender ratio at birth was 117.60 (117.60 boys vs 100 girls) in 2013. A ratio between 100 and 107 is considered normal.

The year 2012 saw 16.4 million births in China, with a birth rate of 1.208 percent, down 0.002 percentage point from 2012, according to the NBS.