Citizens over 60 years of age?will rise?to?31 percent of the whole Chinese population by 2050,?according to Li Baoku, president of the China Aging Development Foundation on Wednesday.

Li said the average rate of "empty nesters" in big cities has reached above 30 percent, with some cities over 50 percent. "The aging population has become a severe social problem which adds to the pressure of maintaining the old."

Li added that to deal with the problem, the country's old-age security system, medical insurance system and subsistence allowance insurance should be increasingly improved.

Currently, China has 169 million?peopleaged above 60, comprising 12.5 percent of the nation's population, according to statistics.